artik710: support Device-Treee Overlay
artik710: support Device-Treee Overlay

This patch enables to support Device-Tree Overlay for artik710.

Change-Id: I3ce9ea7e8fa8a74da2db00962babfc0cecdb57ae
Signed-off-by: Jaewon Kim <46422ecff6e7a995393cb59d2a1bf2c564384889@samsung.com>

SamsungARTIK/build-artik