msm: mdss: Add newly supported writeback formats to MDP driver

Writeback display now supports more MDP formats. This change adds
the definitions for those formats.

CRs-Fixed: 978785
Change-Id: I72fc29a8d7b286b0766c0483ba69d6e02d29b661
Signed-off-by: Benet Clark <benetc@codeaurora.org>