Add DIY ESP32S3 N16R8 E22 Back2back board support

This closes #1.

variants/eastmesh_mqtt/platformio.ini

@@ -863,3 +863,28 @@ build_flags =
 lib_deps =
   ${Xiao_S3_WIO.lib_deps}
   ${esp32_ota.lib_deps}
+
+# https://github.com/VBart/MeshCoreTel-firmware/issues/1
+[env:DIY_ESP32S3_N16R8_E22_Back2back_repeater_mqtt]
+extends = DIY_ESP32S3_N16R8_E22_Back2back
+build_flags =
+  ${DIY_ESP32S3_N16R8_E22_Back2back.build_flags}
+  -D ADVERT_NAME='"DIY ESP32S3 N16R8 E22 Back2back Repeater"'
+  -D ADVERT_LAT=0.0
+  -D ADVERT_LON=0.0
+  -D ADMIN_PASSWORD='"password"'
+  -D MAX_NEIGHBOURS=50
+  -D SX126X_RX_BOOSTED_GAIN=1
+  -D WITH_MQTT_UPLINK=1
+  -D MQTT_DEBUG=1
+  -D WIFI_SSID='"myssid"'
+  -D WIFI_PWD='"mypwd"'
+  -D MQTT_DEFAULT_IATA='"UNSET"'
+  -D CONFIG_MBEDTLS_CERTIFICATE_BUNDLE=1
+build_src_filter = ${DIY_ESP32S3_N16R8_E22_Back2back.build_src_filter}
+  +<../examples/simple_repeater>
+  +<helpers/mqtt/*.cpp>
+  +<helpers/web/*.cpp>
+lib_deps =
+  ${DIY_ESP32S3_N16R8_E22_Back2back.lib_deps}
+  ${esp32_ota.lib_deps}