dcb: fix memory leak

main() dinamically allocates dcb, but when dcb_help() is called it
returns without freeing it.

Fix this using a goto, as it is already done in the same function.

Fixes: 67033d1c1c ("Add skeleton of a new tool, dcb")
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Reviewed-by: Petr Machata <me@pmachata.org>
Signed-off-by: David Ahern <dsahern@kernel.org>

dcb/dcb.c

@@ -571,7 +571,8 @@ int main(int argc, char **argv)
 			break;
 		case 'h':
 			dcb_help();
-			return 0;
+			ret = EXIT_SUCCESS;
+			goto dcb_free;
 		default:
 			fprintf(stderr, "Unknown option.\n");
 			dcb_help();