Use standard types in fopencookie test

Instead of internal __size_t / __off64_t types use ssize_t and off64_t.
This makes it work on musl as well.

build/php.m4

@@ -1464,16 +1464,16 @@ AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <stdio.h>
 
 struct cookiedata {
-  __off64_t pos;
+  off64_t pos;
 };
 
-__ssize_t reader(void *cookie, char *buffer, size_t size)
+ssize_t reader(void *cookie, char *buffer, size_t size)
 { return size; }
-__ssize_t writer(void *cookie, const char *buffer, size_t size)
+ssize_t writer(void *cookie, const char *buffer, size_t size)
 { return size; }
 int closer(void *cookie)
 { return 0; }
-int seeker(void *cookie, __off64_t *position, int whence)
+int seeker(void *cookie, off64_t *position, int whence)
 { ((struct cookiedata*)cookie)->pos = *position; return 0; }
 
 cookie_io_functions_t funcs = {reader, writer, seeker, closer};

main/streams/cast.c

@@ -103,7 +103,7 @@ static ssize_t stream_cookie_writer(void *cookie, const char *buffer, size_t siz
 }
 
 # ifdef COOKIE_SEEKER_USES_OFF64_T
-static int stream_cookie_seeker(void *cookie, __off64_t *position, int whence)
+static int stream_cookie_seeker(void *cookie, off64_t *position, int whence)
 {
 
 	*position = php_stream_seek((php_stream *)cookie, (zend_off_t)*position, whence);