boards: Add sparkfun samd21 dev breakout board

Adding the sparkfun samd21 dev breakout board. This will work with the
basic blinky sample. Link attached to the boards info page.

Link: https://www.sparkfun.com/sparkfun-samd21-dev-breakout.html

Signed-off-by: Rickey Fehr <ric@rf3.xyz>
14 files changed