disp: msm: sde: add trace points for modeset

Adding trace points for the encoder modeset which provides
the duration of modeset when there is a resolution or fps switch.

Change-Id: Idfba792addcb9b68285c8575b62608dec60ca275
Signed-off-by: Lakshmi Narayana Kalavala <lkalaval@codeaurora.org>