The current xmega don't have a way to disable peripherals that are
not in used. Add peripheral management to allow enable only the mcu
blocks that will be used by application. This saves power on active
and sleep modes. By default, at clock initialization, all peripherals
are now disabled and each drive must activate at initialization phase.
The periph_timer and periph_uart were updated with this new feature.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
Add ATxmega common files and cpu definitions.
This works was originally developed by @Josar. The 2018 version
were port to 2021 mainline.
This version changes original port to have only the atxmega CPU
definition. With that, all family can be accomodated.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>