Update the files which contain no license information with the
'Apache-2.0' SPDX license identifier. Many source files in the tree are
missing licensing information, which makes it harder for compliance
tools to determine the correct license.
By default all files without license information are under the default
license of Zephyr, which is Apache version 2.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Convert over arc based boards to use device tree instead of board.h to
describe buttons & LEDs. There are a few boards that the button gpio
flags need validation.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
