git.rc: include winuser.h

winuser.h contains the definition of RT_MANIFEST that our LLVM based
toolchain needs to understand that we want to embed
compat/win32/git.manifest as an application manifest. It currently just
embeds it as additional data that Windows doesn't understand.

This also helps our GCC based toolchain understand that we only want one
copy embedded. It currently embeds one working assembly manifest and one
nearly identical, but useless copy as additional data.

This also teaches our Visual Studio based buildsystem to pick up the
manifest file from git.rc instead of having to explicitly specify it in
contrib/buildsystems/Generators/Vcxproj.pm

This fixes #4707

Signed-off-by: Matthias Aßhauer <mha1993@live.de>

contrib/buildsystems/Generators/Vcxproj.pm

@@ -198,7 +198,6 @@ sub createProject {
       <AdditionalDependencies>\$(VCPKGLibs);\$(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalOptions>invalidcontinue.obj %(AdditionalOptions)</AdditionalOptions>
       <EntryPointSymbol>$entrypoint</EntryPointSymbol>
-      <ManifestFile>$cdup\\compat\\win32\\git.manifest</ManifestFile>
       <SubSystem>$subsystem</SubSystem>
     </Link>
 EOM

git.rc

@@ -1,3 +1,4 @@
+#include<winuser.h>
 1 VERSIONINFO
 FILEVERSION     MAJOR,MINOR,MICRO,PATCHLEVEL
 PRODUCTVERSION  MAJOR,MINOR,MICRO,PATCHLEVEL