Clueboard 66% Hotswap Support (#5204)

* Initial Clueboard 66% arm support

* Fix LAYOUT_66_ansi

* wip

* Bring this branch up to date with led_matrix

* Get Clueboard 66% hotswap working with led_matrix

* stm32 cleanup

* Fix compiling for clueboard 66% hotswap prototype

* Reduce the size of the prototype firmware

keyboards/clueboard/66_hotswap/66_hotswap.h

@@ -3,3 +3,7 @@
 #ifdef KEYBOARD_clueboard_66_hotswap_gen1
     #include "gen1.h"
 #endif
+
+#ifdef KEYBOARD_clueboard_66_hotswap_prototype
+    #include "prototype.h"
+#endif