Allow compilation with mingw64 albeit with warnings due to lack of

	Allow compilation with mingw64 albeit with warnings due to lack of
	%llx/%llu.

	* grub-core/gnulib/msvc-inval.c: Use __cdecl rather than cdecl.
	* grub-core/lib/posix_wrap/wchar.h: Define wint_t.
	* grub-core/lib/posix_wrap/wctype.h: Define wctype_t.
	* include/grub/osdep/hostfile_windows.h: Don't define fseeko/ftello
	on mingw64.
	* include/grub/types.h: Allow sizeof (long) != sizeof (void *).