add LR 2021 to portduino, and allow Framebuffer devices to rotate the screen from config (#11252)

* add LR 2021 to portduino, and allow Framebuffer devices to rotate the screen from config. Requires https://github.com/meshtastic/device-ui/pull/355 and supersedes https://github.com/meshtastic/firmware/pull/10567 and https://github.com/meshtastic/firmware/pull/11138

Many thanks to the original authors https://github.com/a-li3n and https://github.com/jessm33

* Build LR2021Interface.cpp in the wasm env

initLoRa() constructs LR2021Interface for Lora.Module: lr2021, so excluding
the file from the native-wasm source filter left the constructor undefined at
link time. LR20x0Interface.cpp stays excluded; it is template-only and comes in
via the InterfacesTemplates.cpp amalgamation.

Also replace the non-UTF-8 degree signs in the framebuffer rotation comment and
correct the rfswitch alias cleanup comment.

* Trim comments

* Report setenv failure for the framebuffer rotation

variants/native/portduino/platformio.ini

@@ -431,7 +431,8 @@ build_src_filter =
   +<gps/RTC.cpp>
   +<buzz/buzz.cpp> +<buzz/BuzzerFeedbackThread.cpp>
   +<mesh/*.cpp> +<mesh/*.c>
-  -<mesh/LR2021Interface.cpp> -<mesh/LR20x0Interface.cpp>
+  ; template-only, amalgamated into InterfacesTemplates.cpp
+  -<mesh/LR20x0Interface.cpp>
   +<mesh/generated/>
   +<concurrency/>
   +<platform/portduino/PortduinoGlue.cpp> +<platform/portduino/SimRadio.cpp>