Co-Authored-By: Miguel Risco-Castillo <mriscoc@users.noreply.github.com>

codespell -q 3 --builtin=clear,rare,informal,code -S ./Marlin/src/lcd/language -L alo,amin,endcode,stdio,uint

* Consolidate variant scripts
* Rename Marlin-local boards
* Simplify variants where possible
* Rename variants
* CHITU_F103 and MEEB_3DP: Maple platform `platformio-build-stm32f1.py` uses the 'board' name, not 'board_build.variant' so folder names match 'board' and not `board_build.variant`.