msm: mdss: enable tearcheck while entering LP1 state

In current implementation we disable tear check block when
transitioning into ultra low power or power off state for
doze mode. But it is not enabled back when moving from
ultra low power state(LP2) to low power state(LP1), after
which updates are expected. This change enables back tearcheck
block when transitioning to LP1 from LP2 state.

Change-Id: Ic0d8f97752ccf88470da2423f3f8d56a32de227f
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>