sunxi: enable /proc/device-tree - used for board detection

Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
Signed-off-by: Zoltan HERPAI <wigyori@uid0.hu>



git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39972 3c298f89-4303-0410-b956-a3cf2f4a3e73