85xx: Fix enabling of L1 cache parity on secondary cores

Use the same code between primary and secondary cores to init the
L1 cache.  We were not enabling cache parity on the secondary cores.

Also, reworked the L1 cache init code to match the e500mc L2 init code
that first invalidates the cache and locks.  Than enables the cache and
makes sure its enabled before continuing.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>