Add support for ATtiny404

Adds patch for the timers on attiny167

Add support for ATmega164pa

Adds the ATDF file provided from Microchip, and makes changes analog to
290613454fbdc5e4ac98e53deccaf74dafc88963.
This has been tested on real hardware.

Signed-off-by: Tronje Krabbe <tkrabbe@jusst.de>
Signed-off-by: Oskar Munz <omunz@jusst.de>

Add support for attiny13a

Use the same timer patch for atmega1280 as for atmega2560

Add support for ATmega1284p

Add ATmega128RFA1 support

Adds basic ATmega128RFA1 support. Adjusts the common USART patches for
UCSZ? slightly to work with the ATmega128RFA1's ATDF.

Add support for ATtiny1614

Add support for ATtiny816

Add basic support for the ATtiny816 of the tinyAVR1-series.

Add support for ATtiny2313/A

attiny841: Fix TWI:TWSCRB:TWAA enumerated values

Actually this is just a single bit so 2-bit enum values don't make
sense.  Newer svd2rust versions check whether enum values fit which
caught this error.  Fix it.

Add ATtiny167 support

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

all: Drop unnecessary access mode patches

Due to a change in atdf2svd [1], all these access mode patches are no
longer required - they are now translated correctly from the vendor
source file.

Drop all patches which no longer change the output (the code before and
after this change is equivalent when using the new atdf2svd).

[1]: https://github.com/Rahix/atdf2svd/commit/a189276b3540b647fab832946edf0acf39730a0e

Add ATmega8U2

atmega328p, pb: Split EIMSK INT field into 2

The INT0 and INT1 fields in the EIMSK register were incorrectly
combined into a 2 bit field, split into individual bits.

Also allow write access to PRR0 and PRR1 in ATmega328PB.

atmega328p: Make PRR register writable

Fix 16bit timer patch

Add attiny841 and attiny861