feat(gps): Do not start gps if lora region is unset (#10386)

* Disable gps thread on startup if lora region is unset

There is little reason to waste battery on the gps if the data cannot
yet be used.

* fix goobered merge

Refactor GPS enabling logic and remove duplicate code.

* trunk

---------

Co-authored-by: Jonathan Bennett <jbennett@incomsystems.biz>

src/modules/AdminModule.cpp

@@ -1020,6 +1020,14 @@ void AdminModule::handleSetConfig(const meshtastic_Config &c, bool fromOthers)
         }
 #endif
 
+#if !MESHTASTIC_EXCLUDE_GPS
+        // Enable gps if it was previously disabled due to region not being set
+        if (!requiresReboot && config.lora.region != meshtastic_Config_LoRaConfig_RegionCode_UNSET && gps != nullptr &&
+            !gps->isEnabled() && config.position.gps_mode == meshtastic_Config_PositionConfig_GpsMode_ENABLED) {
+            gps->enable();
+        }
+#endif
+
         config.lora = validatedLora; // Finally, return the validated config back to the main config
 
         break;