Add ATtiny202 support
All of the svd patches are in patch/common/attiny-0-series.yaml which should
work for all of the 0-series (but may only work for ATtiny20* and ATtiny40*,
but not 80* or 160* given how the datasheet is split)
Add AT90USB1286 support
Ref: #80
Add attiny841 and attiny861
Add basic support for ATmega4809
Add support for atmega328pb
Add basic support for ATmega644
Add support for the ATtiny84
Add atmega48p device support
Add basic support for ATmega168
Add support for ATmega2560
Add basic support for ATmega64
Pull in the ATDF file from Microchip and add all the necessary plumbing
around the code-base to make it compile. Not tested against real
hardware and no device-specific patches are included yet.
Signed-off-by: Rahix <rahix@rahix.de>