Add ATmega328P Xplained Mini board. The board is an official
development kit from MCHP based on the Arduino UNO, reduced
hardware, with a xplainedmini debugger and CDC ACM serial
converter.
Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>
- Drop duplicated `cpu.c` and `cpu_conf.h`: Those are already provided by
`cpu/atmega_common`.
- The higher values for default stack size of `cpu_conf.h` in
`cpu/atmega_common` results in three tests no longer fitting the available RAM
==> Updated the Makefile.ci to skip linking of those tests for the Arduino
Leonardo
