disp: msm: sde: revert to previous smmu state upon failure to switch

This change saves the previous state before moving into the transitional
smmu state, during secure-display/secure-camera usecases. Upon failure
to complete the transition, set smmu state to the previous state.
Previously, smmu state was staying in transitional state.

Change-Id: I1a78ddcf6ac1c7ea66c8c2095cd1a6d6160647a1
Signed-off-by: Samantha Tran <samtran@codeaurora.org>