Fix potential socket leak at bootstrap and shutdown

This is a follow-up to a39ee0b, found by Coverity Scan.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/api.c

@@ -377,7 +377,7 @@ static void api_cb(uev_t *w, void *arg, int events)
 		case INIT_CMD_SUSPEND:
 			if (runlevel == 0 || runlevel == 6) {
 				warnx("Unsupported command in runlevel S and 6.");
-				return;
+				goto leave;
 			}
 		default:
 			break;