hwc: Avoid idlefallback during video playback

For YUV layer, MDP uses QSEED for chroma upsampling,
using Bilinear filter for chroma plane and CAF for luma
plane.

Only when the filter for luma plane too is Bilinear [along
with programming pixel extension values for luma plane to
correspond to Bilinear filter], there is no difference in
output between MDP and GPU composition.

Since the filter used by MDP is a high-quality filter in
comparision to GPU and that cannot be changed to match the
output of GPU, avoid Idlefallback during video playback
to get rid of MDP-GPU-MDP transitions.

Change-Id: I2d747e9b821de81d9fbdd30c85ff0404f4163ee4
1 file changed