CryptoPkg/OpensslLib: Undefine NO_BUILTIN_VA_FUNCS to fix varargs breakage

CryptoPkg/OpensslLib: Undefine NO_BUILTIN_VA_FUNCS to fix varargs breakage

Instead of patching OpenSSL to add EFIAPI to the one varargs function we
actually *noticed* breakage in, let's fix the problem in a more coherent
way by undefining NO_BUILTIN_VA_FUNCS.

That way, the VA_START and similar macros will actually do the right
thing for non-EFIAPI functions, which is to use the GCC builtins.

It's still fairly broken elsewhere in the tree, with the VA_START macro
being used from both EFIAPI and non-EFIAPI functions — and being broken
in the latter case. We probably ought to make EFIAPI a no-op everywhere
and add -mabi=ms to the GCC builds. But that's a project for another day.
For now, just fix the OpenSSL build in a cleaner fashion.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Qin Long <qin.long@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18705 6f19259b-4bc3-4df7-8a09-765794883524