Tools: DFG: Add information about PCINT and EXT_INT for AVR devices.
Tools: DFG: Add information about PCINT and EXT_INT for AVR devices.

It defines which connected to what GPIO.
This is necessary since Atmel does not specify it in the part
description files. (Bad Atmel!)

chrism333/xpcc,chrism333/xpcc,dergraaf/xpcc,chrism333/xpcc,dergraaf/xpcc,dergraaf/xpcc,dergraaf/xpcc,chrism333/xpcc