msm: mdss: fix rotator failures when pixel format changes

Current code fails the SMP allocation in the rotator session
when the pixel format during the session changes from YUV to
RGB. Fix these failures by releasing the SMP allocation
if pixel format changes.

Change-Id: Ic051ad4c48be6d4998d392fa74f7b3fb2c131980
Signed-off-by: Ingrid Gallardo <ingridg@codeaurora.org>