boards: arm: Introduce Google Dragonclaw Development Board

Dragonclaw is a board created by Google for fingerprint-related
functionality development. Board schematics, layout and BOM is
available at:
https://chromium.googlesource.com/chromiumos/platform/ec/+/HEAD/docs/schematics/dragonclaw



Signed-off-by: Patryk Duda <pdk@semihalf.com>