drm/i915: Introduce with_intel_display_power_if_enabled()

Add the _if_enabled() counterpart to with_intel_display_power().
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210913144440.23008-7-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/intel_display_power.h

@@ -410,6 +410,10 @@ void gen9_dbuf_slices_update(struct drm_i915_private *dev_priv,
 	for ((wf) = intel_display_power_get((i915), (domain)); (wf); \
 	     intel_display_power_put_async((i915), (domain), (wf)), (wf) = 0)
 
+#define with_intel_display_power_if_enabled(i915, domain, wf) \
+	for ((wf) = intel_display_power_get_if_enabled((i915), (domain)); (wf); \
+	     intel_display_power_put_async((i915), (domain), (wf)), (wf) = 0)
+
 void chv_phy_powergate_lanes(struct intel_encoder *encoder,
 			     bool override, unsigned int mask);
 bool chv_phy_powergate_ch(struct drm_i915_private *dev_priv, enum dpio_phy phy,