drm/msm: delete conversion from bool value to bool return

Delete the conversion from bool value to bool function return.

Signed-off-by: Bernard Zhao <bernard@vivo.com>
Link: https://lore.kernel.org/r/AI*ANACSDfnjQejyeNXUnKoQ.1.1604995827401.Hmail.bernard@vivo.com


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>