zeus: reduce pmems to reclaim some more RAM, eliminate audio_pmem since it's not being used

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: I9e44cf321b3de079fbb7d0fdbecb9c40de3b8789
update zeus-board thanks @mikeNG

Change-Id: Ic865590a84923c9afb4a2d261ffbb494e1659c01