Pass rtc_clock to all MicroNMEALocationProvider instances

Enable GPS time synchronization across all variants by passing
&rtc_clock to MicroNMEALocationProvider. When GPS gets a valid
fix, the RTC clock is now updated automatically every 30 minutes.

Updated 16 variants: rak4631, lilygo_tbeam_SX1262, rak_wismesh_tag,
lilygo_tbeam_supreme_SX1262, thinknode_m3, heltec_v4, thinknode_m1,
lilygo_tbeam_SX1276, meshadventurer, nano_g2_ultra, heltec_v3,
promicro, xiao_c3, heltec_tracker_v2, keepteen_lt1, heltec_mesh_solar.

variants/nano_g2_ultra/target.cpp

@@ -12,7 +12,7 @@ WRAPPER_CLASS radio_driver(radio, board);
 
 VolatileRTCClock fallback_clock;
 AutoDiscoverRTCClock rtc_clock(fallback_clock);
-MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1);
+MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1, &rtc_clock);
 NanoG2UltraSensorManager sensors = NanoG2UltraSensorManager(nmea);
 
 #ifdef DISPLAY_CLASS