drm/msm: drop pm ops from the headless msm driver

The msm_pm_prepare()/msm_pm_complete() only make sense for the
KMS-enabled devices, they have priv->kms guards inside. Drop global
msm_pm_ops, which were used only by the headless msm device.
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/561643/Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_drv.c

@@ -1120,11 +1120,6 @@ void msm_pm_complete(struct device *dev)
 	drm_mode_config_helper_resume(ddev);
 }
 
-static const struct dev_pm_ops msm_pm_ops = {
-	.prepare = msm_pm_prepare,
-	.complete = msm_pm_complete,
-};
-
 /*
  * Componentized driver support:
  */
@@ -1305,7 +1300,6 @@ static struct platform_driver msm_platform_driver = {
 	.shutdown   = msm_drv_shutdown,
 	.driver     = {
 		.name   = "msm",
-		.pm     = &msm_pm_ops,
 	},
 };