drm/i915: Check the clock from adjusted mode in intel_crtc_active()

The clock in crtc->mode doesn't necessarily mean anything. Let's look
at the clock in adjusted_mode instead.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_pm.c

@@ -45,10 +45,13 @@
 
 static bool intel_crtc_active(struct drm_crtc *crtc)
 {
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+
 	/* Be paranoid as we can arrive here with only partial
 	 * state retrieved from the hardware during setup.
 	 */
-	return to_intel_crtc(crtc)->active && crtc->fb && crtc->mode.clock;
+	return intel_crtc->active && crtc->fb &&
+		intel_crtc->config.adjusted_mode.clock;
 }
 
 static void i8xx_disable_fbc(struct drm_device *dev)