brcm47xx: use old partition names again for kernel 3.8

This fixes sysupgrade. The partition names are used all over the Internet in various howtos.

Thank you russell for spotting this problem.


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@36235 3c298f89-4303-0410-b956-a3cf2f4a3e73