msm7x27a-common: allow unknown source by default

Change-Id: Ief73df3a49b455e2d675158bb0e277faee391857
msm7x27a-common: sync msm_mdp header with kernel

Change-Id: I1a08ee47be672285ca0e0976d1da01991b85d4a0
msm7x27a-common: Get rid of using reserved fields

Change-Id: I9834d456cb15917c5d45b46c34f8cf3e9bf40973