Arduino mode fails to open on emacs27

[ChillarAnand]

Eval error in the ‘c-lang-defconst’ for ‘c-constant-kwds’ in arduino-mode:
Eval error in the ‘c-lang-defconst’ for ‘c-basic-matchers-before’ in arduino-mode:
Eval error in the ‘c-lang-defconst’ for ‘c-matchers-2’ in arduino-mode:
Invalid function: (append (quote ("HIGH" "LOW" "INPUT" "OUTPUT" "INPUT_PULLUP" "LED_BUILTIN" "true" "false")) (c-get-lang-constant (quote c-constant-kwds) (quote (cc-langs))))