[Crossfire] Telemetry new fields (GPS / Battery)

I did a refactoring for the latitude and longitude decoding which should be tested carefully for FrSky S.PORT and D telemetry
There was a double conversion in S.PORT protocol, there are less maths now, and perhaps precision will be better

radio/src/telemetry/telemetry.cpp

@@ -63,8 +63,10 @@ lcdint_t applyChannelRatio(source_t channel, lcdint_t val)
 void processTelemetryData(uint8_t data)
 {
 #if defined(CROSSFIRE)
-  if (telemetryProtocol == PROTOCOL_PULSES_CROSSFIRE)
+  if (telemetryProtocol == PROTOCOL_PULSES_CROSSFIRE) {
     processCrossfireTelemetryData(data);
+    return;
+  }
 #endif
   processFrskyTelemetryData(data);
 }