curl 7.56 deprecations

[matheusfillipe]

# github.com/andelf/go-curl
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go: In function ‘curl_formadd_name_content_length’:
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:40:5: warning: ‘curl_formadd’ is deprecated: since 7.56.0. Use curl_mime_init() [-Wdeprecated-declarations]
   40 |     return curl_formadd(httppost, last_post,
      |     ^~~~~~
In file included from ../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:5:
/usr/include/curl/curl.h:2570:1: note: declared here
 2570 | curl_formadd(struct curl_httppost **httppost,
      | ^~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:41:25: warning: ‘CURLFORM_COPYNAME’ is deprecated: since 7.56.0. Use curl_mime_name() [-Wdeprecated-declarations]
   41 |                         CURLFORM_COPYNAME, name,
      |                         ^~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2495:3: note: declared here
 2495 |   CURLFORM_COPYNAME        CURL_DEPRECATED(7.56.0, "Use curl_mime_name()"),
      |   ^~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:42:25: warning: ‘CURLFORM_COPYCONTENTS’ is deprecated: since 7.56.0. Use curl_mime_data() [-Wdeprecated-declarations]
   42 |                         CURLFORM_COPYCONTENTS, content,
      |                         ^~~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2498:3: note: declared here
 2498 |   CURLFORM_COPYCONTENTS    CURL_DEPRECATED(7.56.0, "Use curl_mime_data()"),
      |   ^~~~~~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:43:25: warning: ‘CURLFORM_CONTENTSLENGTH’ is deprecated: since 7.56.0. Use curl_mime_data() [-Wdeprecated-declarations]
   43 |                         CURLFORM_CONTENTSLENGTH, length, CURLFORM_END);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2500:3: note: declared here
 2500 |   CURLFORM_CONTENTSLENGTH  CURL_DEPRECATED(7.56.0, "Use curl_mime_data()"),
      |   ^~~~~~~~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go: In function ‘curl_formadd_name_content_length_type’:
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:47:5: warning: ‘curl_formadd’ is deprecated: since 7.56.0. Use curl_mime_init() [-Wdeprecated-declarations]
   47 |     return curl_formadd(httppost, last_post,
      |     ^~~~~~
/usr/include/curl/curl.h:2570:1: note: declared here
 2570 | curl_formadd(struct curl_httppost **httppost,
      | ^~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:48:25: warning: ‘CURLFORM_COPYNAME’ is deprecated: since 7.56.0. Use curl_mime_name() [-Wdeprecated-declarations]
   48 |                         CURLFORM_COPYNAME, name,
      |                         ^~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2495:3: note: declared here
 2495 |   CURLFORM_COPYNAME        CURL_DEPRECATED(7.56.0, "Use curl_mime_name()"),
      |   ^~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:49:25: warning: ‘CURLFORM_COPYCONTENTS’ is deprecated: since 7.56.0. Use curl_mime_data() [-Wdeprecated-declarations]
   49 |                         CURLFORM_COPYCONTENTS, content,
      |                         ^~~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2498:3: note: declared here
 2498 |   CURLFORM_COPYCONTENTS    CURL_DEPRECATED(7.56.0, "Use curl_mime_data()"),
      |   ^~~~~~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:50:25: warning: ‘CURLFORM_CONTENTSLENGTH’ is deprecated: since 7.56.0. Use curl_mime_data() [-Wdeprecated-declarations]
   50 |                         CURLFORM_CONTENTSLENGTH, length,
      |                         ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2500:3: note: declared here
 2500 |   CURLFORM_CONTENTSLENGTH  CURL_DEPRECATED(7.56.0, "Use curl_mime_data()"),
      |   ^~~~~~~~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:51:25: warning: ‘CURLFORM_CONTENTTYPE’ is deprecated: since 7.56.0. Use curl_mime_type() [-Wdeprecated-declarations]
   51 |                         CURLFORM_CONTENTTYPE, type, CURLFORM_END);
      |                         ^~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2510:3: note: declared here
 2510 |   CURLFORM_CONTENTTYPE     CURL_DEPRECATED(7.56.0, "Use curl_mime_type()"),
      |   ^~~~~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go: In function ‘curl_formadd_name_file_type’:
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:55:5: warning: ‘curl_formadd’ is deprecated: since 7.56.0. Use curl_mime_init() [-Wdeprecated-declarations]
   55 |     return curl_formadd(httppost, last_post,
      |     ^~~~~~
/usr/include/curl/curl.h:2570:1: note: declared here
 2570 | curl_formadd(struct curl_httppost **httppost,
      | ^~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:56:25: warning: ‘CURLFORM_COPYNAME’ is deprecated: since 7.56.0. Use curl_mime_name() [-Wdeprecated-declarations]
   56 |                         CURLFORM_COPYNAME, name,
      |                         ^~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2495:3: note: declared here
 2495 |   CURLFORM_COPYNAME        CURL_DEPRECATED(7.56.0, "Use curl_mime_name()"),
      |   ^~~~~~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:57:25: warning: ‘CURLFORM_FILE’ is deprecated: since 7.56.0. Use curl_mime_filedata() [-Wdeprecated-declarations]
   57 |                         CURLFORM_FILE, filename,
      |                         ^~~~~~~~~~~~~
/usr/include/curl/curl.h:2504:3: note: declared here
 2504 |   CURLFORM_FILE            CURL_DEPRECATED(7.56.0, "Use curl_mime_filedata()"),
      |   ^~~~~~~~~~~~~
../../go/pkg/mod/github.com/andelf/go-curl@v0.0.0-20200630032108-fd49ff24ed97/easy.go:58:25: warning: ‘CURLFORM_CONTENTTYPE’ is deprecated: since 7.56.0. Use curl_mime_type() [-Wdeprecated-declarations]
   58 |                         CURLFORM_CONTENTTYPE, type, CURLFORM_END);
      |                         ^~~~~~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:2510:3: note: declared here
 2510 |   CURLFORM_CONTENTTYPE     CURL_DEPRECATED(7.56.0, "Use curl_mime_type()"),
      |   ^~~~~~~~~~~~~~~~~~~~