ARM: dts: msm: enable dynamic fps for nt35597 truly panel on sdm660

This reverts commit e3558074 ("ARM: dts:
msm: disable dynamic fps for nt35597 truly panel on sdm660").

Adding back dynamic fps support for nt35597 truly panel, since the
display split screen issue is root caused to be related to DSI BTA
operation.

Change-Id: If020eb482b3e53ea114365734663a8c14c37dc14
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>