Adds support for Purism coreboot keyboards

On Purism coreboot systems the quirks mode in atkbdc prevents built in
Keyboard from being used. Add quirk to prevent that.

MFC After: 2 weeks
PR: 271737
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D40405

(cherry picked from commit 599a4548f8f1758afe1d33c53e9a56e42c5f3e30)