Clean up PID language defines

Marlin/src/lcd/language/language_cz.h

Marlin/src/lcd/language/language_de.h

Marlin/src/lcd/language/language_el_gr.h

Marlin/src/lcd/language/language_en.h

Marlin/src/lcd/language/language_it.h

Marlin/src/lcd/language/language_jp_kana.h

Marlin/src/lcd/language/language_pl.h

Marlin/src/lcd/language/language_ru.h

Marlin/src/lcd/language/language_sk.h

Marlin/src/lcd/language/language_uk.h

Marlin/src/lcd/language/language_vi.h

Marlin/src/lcd/language/language_zh_CN.h

Marlin/src/lcd/language/language_zh_TW.h