Clean up file descriptors when calling hooks.

When calling post-update hook, don't leave stdin and stdout connected to
the pushing connection.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

run-command.h

@@ -11,6 +11,9 @@ enum {
 	ERR_RUN_COMMAND_WAITPID_NOEXIT,
 };
 
+#define RUN_COMMAND_NO_STDIO 1
+
+int run_command_v_opt(int argc, char **argv, int opt);
 int run_command_v(int argc, char **argv);
 int run_command(const char *cmd, ...);