Disable the GPS thread after factory reset has been requested

src/gps/GPS.cpp

@@ -439,8 +439,7 @@ int32_t GPS::runOnce()
                 LOG_DEBUG("GPS is not communicating, trying factory reset on next bootup.\n");
                 devicestate.did_gps_reset = false;
                 nodeDB.saveDeviceStateToDisk();
-                notifyGPSSleep.notifyObservers(NULL);
-                forceWake(false);
+                disable(); // Stop the GPS thread as it can do nothing useful until next reboot.
             }
         }
     }