drm/i915/hdmi: Enable hdmi mode on g4x, too

For compliance we really should be sending NULL infoframes always
when we detect a hdmi capable monitor. Also remove the now redudant
setting for the has_audio case and enforce that audio is only
possible with a hdmi sink.
Reviewed-by: NNaresh Kumar Kachhi <naresh.kumar.kachhi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_hdmi.c

@@ -650,15 +650,14 @@ static void intel_hdmi_mode_set(struct intel_encoder *encoder)
 	else
 		hdmi_val |= SDVO_COLOR_FORMAT_8bpc;
 
-	if (intel_hdmi->has_hdmi_sink &&
-	    (HAS_PCH_CPT(dev) || IS_VALLEYVIEW(dev)))
+	if (intel_hdmi->has_hdmi_sink)
 		hdmi_val |= HDMI_MODE_SELECT_HDMI;
 
 	if (intel_hdmi->has_audio) {
+		WARN_ON(!intel_hdmi->has_hdmi_sink);
 		DRM_DEBUG_DRIVER("Enabling HDMI audio on pipe %c\n",
 				 pipe_name(crtc->pipe));
 		hdmi_val |= SDVO_AUDIO_ENABLE;
-		hdmi_val |= HDMI_MODE_SELECT_HDMI;
 		intel_write_eld(&encoder->base, adjusted_mode);
 	}