ARM: dts: msm: enable dynamic fps for SM6150

Enabling dynamic fps for hx83112a truly dsi
video panels on SM6150. The feature helps to reduce fps
when static screen leading to power saving.

Change-Id: I719d809997067492c1130e95fc099d8fb22b3bba
Signed-off-by: Raviteja Tamatam <travitej@codeaurora.org>