ARM: dts: msm: add nt35597 sharp panel node for sdm660

Add nt35597 sharp video and command mode panel node to
sdm660 target.
Also enable NULL packet insertion for DSI controller
to avoid corruption seen with nt35597 sharp panel.

Change-Id: I42813cecd68059f835810cd015cd6654c3507dfa
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>