Change the Station G2 default tx power

set the default TX power to 7dBm to avoid illegal power output by default.

variants/station_g2/platformio.ini

@@ -16,7 +16,8 @@ build_flags =
   -D P_LORA_SCLK=12
   -D P_LORA_MISO=14
   -D P_LORA_MOSI=13
-  -D LORA_TX_POWER=19
+  -D LORA_TX_POWER=7 ; configured as 7dbm, because the final output will be ~27dbm (~0.5w) if the PA is enabled.
+  -D MAX_LORA_TX_POWER=19 ; max output without burning out the PA
 ;  -D P_LORA_TX_LED=35
   -D PIN_BOARD_SDA=5
   -D PIN_BOARD_SCL=6