mpc83xx: add support for kernel 3.14

This is compile tested only, please run test and report back.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@43797 3c298f89-4303-0410-b956-a3cf2f4a3e73