ARM: dts: msm: update timing db property for MDSS nodes

For some platforms due to HW limitation timing db property
can not be a shared property, so making this property as interface
specific for MDSS, instead of shared.

Change-Id: I6e1a482dd23f475c332200f857494a7c848c58c1
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>