boards: atmel: Fix devicetree style

The Zephyr is implementing a linter to catch devicetree problems. This
boards comments are exceptions and are formatted to be compliance with
the linter. However due to the exception the linter check was disabled
to avoid undesirable formatting and keep the original details in the
comments.

Signed-off-by: Gerson Fernando Budke <nandojve@gmail.com>