git: s/run_command/run_builtin/

There is a static function called run_command which
conflicts with the library function in run-command.c; this
isn't a problem currently, but prevents including
run-command.h in git.c.

This patch just renames the static function to something
more specific and non-conflicting.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git.c

@@ -219,7 +219,7 @@ struct cmd_struct {
 	int option;
 };
 
-static int run_command(struct cmd_struct *p, int argc, const char **argv)
+static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 {
 	int status;
 	struct stat st;
@@ -384,7 +384,7 @@ static void handle_internal_command(int argc, const char **argv)
 		struct cmd_struct *p = commands+i;
 		if (strcmp(p->cmd, cmd))
 			continue;
-		exit(run_command(p, argc, argv));
+		exit(run_builtin(p, argc, argv));
 	}
 }