Remove code tagged APT_PKG_590, add some missing includes

Remove all code scheduled to be removed after 5.90, and fix
files to include files they previously got from hashes.h
including more headers.

apt-pkg/contrib/error.h

@@ -362,6 +362,6 @@ class GlobalError							/*{{{*/
 GlobalError *_GetErrorObj();
 static struct {
 	inline GlobalError* operator ->() { return _GetErrorObj(); }
-} _error APT_UNUSED APT_PKG_590("Consider rewriting this");
+} _error APT_UNUSED;
 
 #endif

apt-pkg/contrib/hashes.cc

@@ -16,6 +16,7 @@
 #include <apt-pkg/fileutl.h>
 #include <apt-pkg/hashes.h>
 #include <apt-pkg/macros.h>
+#include <apt-pkg/strutl.h>
 
 #include <algorithm>
 #include <iostream>

apt-pkg/contrib/hashes.h

@@ -13,12 +13,10 @@
 #define APTPKG_HASHES_H
 
 #include <apt-pkg/macros.h>
-#include <apt-pkg/md5.h>
-#include <apt-pkg/sha1.h>
-#include <apt-pkg/sha2.h>
 
 #include <cstring>
 #include <string>
+#include <vector>
 
 
 
@@ -171,15 +169,6 @@ class PrivateHashes;
 class Hashes
 {
    PrivateHashes * const d;
-APT_IGNORE_DEPRECATED_PUSH
-   /* TODO: those will disappear in the future as it is hard to add new ones this way.
-    * Use Add* to build the results and get them via GetHashStringList() instead */
-   MD5Summation MD5 APT_PKG_590("Remove");
-   SHA1Summation SHA1 APT_PKG_590("Remove");
-   SHA256Summation SHA256 APT_PKG_590("Remove");
-   SHA512Summation SHA512 APT_PKG_590("Remove");
-APT_IGNORE_DEPRECATED_POP
-
    public:
    static const int UntilEOF = 0;
 

apt-pkg/contrib/macros.h

@@ -121,13 +121,6 @@
 #define APT_PKG_RELEASE 0
 #define APT_PKG_ABI ((APT_PKG_MAJOR * 100) + APT_PKG_MINOR)
 
-
-#if APT_PKG_ABI > 590
-#define APT_PKG_590(msg)  __attribute__((error(msg)))
-#else
-#define APT_PKG_590(msg)
-#endif
-
 /* Should be a multiple of the common page size (4096) */
 static constexpr unsigned long long APT_BUFFER_SIZE = 64 * 1024;