kernel: fix mpcore watchdog symbol export

git-svn-id: svn://svn.openwrt.org/openwrt@35907 3c298f89-4303-0410-b956-a3cf2f4a3e73
cns3xxx: add linux 3.8 support and use it by default

git-svn-id: svn://svn.openwrt.org/openwrt@35908 3c298f89-4303-0410-b956-a3cf2f4a3e73