This saves 444 bytes on the pygamer build (both commits taken together)
testing performed:
* pygamer (samd51) with ShiftRegisterKeys
* macropad (rp2040) with Keys
* UM feather s2 (esp32-s2) with KeyMatrix
Result:
* all ports still worked nicely
* keys held down at start always registered (>2 trials all boards, >100 trials esp32-s2)
* keys held down are immediately registered after reset() (>100 trials esp32-s2)
* double .reset() is OK, accessing .events throws (only tested esp32-s2)
