ARM: dts: msm: disable partial update for msm8992

Temporarily disable partial update feature for msm8992 until
support is added for the feature with ping pong split configured
for dual DSI panels.

Change-Id: Iac0acfdb0df3df794d704108e6fdbf7820ffec7c
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>