board: tbs2910: Add device tree

... as preparation for additional driver model coonversions.

We use CONFIG_OF_EMBED here to keep u-boot.imx as final binary name. So we
maintain compatibility with the original TBS u-boot and available HOWTOs
for u-boot updates.

Signed-off-by: Soeren Moch <smoch@web.de>
diff --git a/board/tbs/tbs2910/MAINTAINERS b/board/tbs/tbs2910/MAINTAINERS
index bf17655..a3ad2f7 100644
--- a/board/tbs/tbs2910/MAINTAINERS
+++ b/board/tbs/tbs2910/MAINTAINERS
@@ -1,6 +1,7 @@
 TBS2910 BOARD
 M:	Soeren Moch <smoch@web.de>
 S:	Maintained
+F:	arch/arm/dts/imx6q-tbs2910.dts
 F:	board/tbs/tbs2910/
 F:	configs/tbs2910_defconfig
 F:	include/configs/tbs2910.h