drm/i915: Remove set but not used variable 'intel_dig_port'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpu/drm/i915/display/intel_ddi.c: In function 'intel_ddi_get_config':
drivers/gpu/drm/i915/display/intel_ddi.c:3774:29: warning:
 variable 'intel_dig_port' set but not used [-Wunused-but-set-variable]
  struct intel_digital_port *intel_dig_port;

It is never used, so can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190705113138.65880-1-yuehaibing@huawei.com

drivers/gpu/drm/i915/display/intel_ddi.c

@@ -3771,7 +3771,6 @@ void intel_ddi_get_config(struct intel_encoder *encoder,
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
 	struct intel_crtc *intel_crtc = to_intel_crtc(pipe_config->base.crtc);
 	enum transcoder cpu_transcoder = pipe_config->cpu_transcoder;
-	struct intel_digital_port *intel_dig_port;
 	u32 temp, flags = 0;
 
 	/* XXX: DSI transcoder paranoia */
@@ -3810,7 +3809,6 @@ void intel_ddi_get_config(struct intel_encoder *encoder,
 	switch (temp & TRANS_DDI_MODE_SELECT_MASK) {
 	case TRANS_DDI_MODE_SELECT_HDMI:
 		pipe_config->has_hdmi_sink = true;
-		intel_dig_port = enc_to_dig_port(&encoder->base);
 
 		pipe_config->infoframes.enable |=
 			intel_hdmi_infoframes_enabled(encoder, pipe_config);