[PATCH] main.cpp: fix broken build for libgit2 0.21

[Gaetan Bisson]

[2014-12-06 15:48:03 +0200] Lubomir I. Ivanov:
> +#if !LIBGIT2_VER_MAJOR && LIBGIT2_VER_MINOR <= 20 && !defined(USE_LIBGIT21_API)	

This breaks building against libgit2 for me:

	main.cpp: In function 'int main(int, char**)':
	main.cpp:48:19: error: 'git_libgit2_init' was not declared in this scope
	  git_libgit2_init();
	                   ^
	Makefile:1198: recipe for target '.obj/main.o' failed

I'm running an up-to-date Arch Linux system with libgit2-0.21.1;
git2/version.h has:

	#define LIBGIT2_VERSION "0.21.0"
	#define LIBGIT2_VER_MAJOR 0
	#define LIBGIT2_VER_MINOR 21
	#define LIBGIT2_VER_REVISION 0

and USE_LIBGIT21_API is nowhere defined...

Cheers.

-- 
Gaetan