blsd: fix cross-compilation

pkgs/tools/misc/blsd/default.nix

···
 
   goDeps = ./deps.nix;
 
-  nativeBuildInputs = [ pkgconfig libgit2 ];
+  nativeBuildInputs = [ pkgconfig ];
+  buildInputs = [ libgit2 ];
 
   meta = with stdenv.lib; {
     homepage = https://github.com/junegunn/blsd;