Merge DPU changes, resolving conflicts between branches. Full changelog
will be present in the final merge commit.

DPU:
 - DSPP sub-block flush on sc7280
 - support AR30 in addition to XR30 format
 - Allow using REC_0 and REC_1 to handle wide (4k) RGB planes
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>