sde: Allocate the rotator buffers after bandwidth checks

1. Allocate the rotator buffers after scale data configuration and
bandwidth checks, to make sure that allocation happens only for a
successful strategy.
2. Rotator ouput format needs to consider downscale for NV12_UBWC.
3. Add support for NV12_UBWC pixel format in SDE utility functions.

Change-Id: Ic1f781d5076816a3d365f3763ebd929a32767797
6 files changed