drm/i915: use enc_to_intel_dp() instead of opencoding the same

Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 6096871..b1f50b1 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -620,19 +620,17 @@
 	return to_intel_connector(connector)->encoder;
 }
 
-static inline struct intel_dp *enc_to_intel_dp(struct drm_encoder *encoder)
-{
-	struct intel_digital_port *intel_dig_port =
-		container_of(encoder, struct intel_digital_port, base.base);
-	return &intel_dig_port->dp;
-}
-
 static inline struct intel_digital_port *
 enc_to_dig_port(struct drm_encoder *encoder)
 {
 	return container_of(encoder, struct intel_digital_port, base.base);
 }
 
+static inline struct intel_dp *enc_to_intel_dp(struct drm_encoder *encoder)
+{
+	return &enc_to_dig_port(encoder)->dp;
+}
+
 static inline struct intel_digital_port *
 dp_to_dig_port(struct intel_dp *intel_dp)
 {