display: Add support for MDP Composition

This change
   1) implements MDP Composition upto 3 layers
   2) adds invalidator support to fall back to FB
      composition during idle screen condition.

Change-Id: I55f27321fd0df096b353d66aaad1cc720cd4b84b
Acked-by: Jeykumar Sankaran <jsanka@codeaurora.org>
8 files changed