Fix double-close, found by Coverity Scan

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

src/service.c

@@ -721,12 +721,12 @@ static int service_start(svc_t *svc)
 			}
 			/* fallthrough */
 		case SVC_NOTIFY_S6:
-			close(fd); /* client-end of pipefd for s6 notify */
+			if (svc->notify == SVC_NOTIFY_S6)
+				close(fd); /* client-end of pipefd for s6 notify */
+
 			result = uev_io_init(ctx, &svc->notify_watcher, service_notify_cb, svc, sd, UEV_READ);
 			if (result < 0) {
 				err(1, "%s: failed setting up notify callback", svc_ident(svc, NULL, 0));
-				if (svc->notify == SVC_NOTIFY_S6)
-					close(fd);
 				close(sd);
 				break;
 			}