Clean up BOARD_NAME in pins

Marlin/src/pins/pins_3DRAG.h

Marlin/src/pins/pins_ARMED.h

Marlin/src/pins/pins_AZTEEG_X5_GT.h

Marlin/src/pins/pins_AZTEEG_X5_MINI_WIFI.h

Marlin/src/pins/pins_BEAST.h

Marlin/src/pins/pins_BLACK_STM32F407VE.h

Marlin/src/pins/pins_CHITU3D.h

Marlin/src/pins/pins_DUPLICATOR_I3_PLUS.h

Marlin/src/pins/pins_FORMBOT_RAPTOR.h

Marlin/src/pins/pins_FORMBOT_RAPTOR2.h

Marlin/src/pins/pins_FORMBOT_TREX2PLUS.h

Marlin/src/pins/pins_FORMBOT_TREX3.h

Marlin/src/pins/pins_FYSETC_CHEETAH.h

Marlin/src/pins/pins_GTM32_PRO_VB.h

Marlin/src/pins/pins_K8400.h

Marlin/src/pins/pins_K8800.h

Marlin/src/pins/pins_MAKEBOARD_MINI.h

Marlin/src/pins/pins_MALYAN_M200.h

Marlin/src/pins/pins_MEGATRONICS_2.h

Marlin/src/pins/pins_MIGHTYBOARD_REVE.h