device: preserve assume state if updating port fails

If we fail to update the port connection, don't forget the assume
state but try again later. This helps when assuming a team connection
and its ports: the ports may fail to generate a connection because
teamd was not started yet; in that case we need to try again.

https://bugzilla.redhat.com/show_bug.cgi?id=2092215
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1523
(cherry picked from commit 27ad228df1)
(cherry picked from commit c273962a73)

src/core/devices/nm-device.c

@@ -8565,6 +8565,7 @@ nm_device_generate_connection(NMDevice *self,
                         nm_device_get_iface(master),
                         local->message);
             g_error_free(local);
+            NM_SET_OUT(out_maybe_later, TRUE);
             return NULL;
         }
     } else {