drm/i915/dp: debug log whether backlight is being enabled or disabled

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0b504c4..74a59b3 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1481,7 +1481,8 @@
 	if (is_enabled == enable)
 		return;
 
-	DRM_DEBUG_KMS("\n");
+	DRM_DEBUG_KMS("panel power control backlight %s\n",
+		      enable ? "enable" : "disable");
 
 	if (enable)
 		_intel_edp_backlight_on(intel_dp);