* refactored platformio.ini, breaking up into variants/*.ini files

variants/xiao_c3/platformio.ini

@@ -0,0 +1,50 @@
+[Xiao_esp32_C3]
+extends = esp32_base
+board = seeed_xiao_esp32c3
+build_flags =
+  ${esp32_base.build_flags}
+  -D LORA_TX_BOOST_PIN=D3
+  -D P_LORA_TX_LED=D5
+  -D PIN_VBAT_READ=D0
+  -D P_LORA_DIO_1=D2
+  -D P_LORA_NSS=D4
+  -D P_LORA_RESET=RADIOLIB_NC
+  -D P_LORA_BUSY=D1
+  -D PIN_BOARD_SDA=D6
+  -D PIN_BOARD_SCL=D7
+  -D SX126X_DIO2_AS_RF_SWITCH=true
+  -D SX126X_DIO3_TCXO_VOLTAGE=1.8
+  -D SX126X_CURRENT_LIMIT=130.0f  ; for best TX power!
+
+[env:Xiao_C3_Repeater_sx1262]
+extends = Xiao_esp32_C3
+build_src_filter = ${Xiao_esp32_C3.build_src_filter}
+  +<../examples/simple_repeater/main.cpp>
+build_flags =
+  ${Xiao_esp32_C3.build_flags}
+  -D RADIO_CLASS=CustomSX1262
+  -D WRAPPER_CLASS=CustomSX1262Wrapper
+  -D SX126X_RX_BOOSTED_GAIN=1
+  -D LORA_TX_POWER=22
+  -D ADVERT_NAME='"Xiao Repeater"'
+  -D ADVERT_LAT=-37.0
+  -D ADVERT_LON=145.0
+  -D ADMIN_PASSWORD='"password"'
+;  -D MESH_PACKET_LOGGING=1
+;  -D MESH_DEBUG=1
+
+[env:Xiao_C3_Repeater_sx1268]
+extends = Xiao_esp32_C3
+build_src_filter = ${Xiao_esp32_C3.build_src_filter}
+  +<../examples/simple_repeater/main.cpp>
+build_flags =
+  ${Xiao_esp32_C3.build_flags}
+  -D RADIO_CLASS=CustomSX1268
+  -D WRAPPER_CLASS=CustomSX1268Wrapper
+  -D LORA_TX_POWER=22
+  -D ADVERT_NAME='"Xiao Repeater"'
+  -D ADVERT_LAT=-37.0
+  -D ADVERT_LON=145.0
+  -D ADMIN_PASSWORD='"password"'
+ ; -D MESH_PACKET_LOGGING=1
+ ; -D MESH_DEBUG=1