AvrPins: add definitions for ports up to L
AvrPins: add definitions for ports up to L

ambrop72/aprinter,johnkingsley/aprinter,fixator/aprinter,ambrop72/aprinter,fixator/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,fixator/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,fixator/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,fixator/aprinter,fixator/aprinter