Use pin_checklist[] of size N_PINS instead N_PINS - 1, to avoid future
problems. Also remove pins_check from set_pin; instead use mask[0] == 0
to check wether to do something or not.
avrftdi_private.h: Change size of pin_checklist[] to N_PINS.
avrftdi.c: Adapt code to new size of pin_checklist. Remove pins_check
from set_pin.
git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk@1170 81a1dc3b-b13d-400b-aceb-764788c761c2