wl12xx: update fw status struct

Update the fw status struct according to the new fw api
(fw >= 6/7.0.0.35).
All the roles use the same struct now.

The memory accounting was changed a bit according to
the struct changes.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>