bcm53xx: activate some workarounds for errors in the Cortex-A9

BCM4708 uses a Cortex-A9 rev r3p0 and a L2C-310 rev r3p2.

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


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@42690 3c298f89-4303-0410-b956-a3cf2f4a3e73