Revert "OMAP4: do not force workarounds for errata fixed in 4460"

This reverts commit b87599bc9a52b2849ac9c36bd936f7afa8ae268a.
Revert "Tuna: set PL310 cache controller prefetch offset to 3"

This reverts commit 86d8e19a80bf557f5da26821ab40b934b67d9336.
FIX: RCU_FAN value corrected