overlay: Swap flips on 90 only for older mdp version.

Older mdp rotator does 90 first and flip next,
forcing HAL to swap flips, in presence of 90.

Newer mdp does flip first and 90 next, owing to DMA pipe.
(Also similar to GPU flip handling). So we can pass flips as-is.

Change-Id: I379509a07e45966262005666e7727e7923079d3a