drm/i915: Allow stereo modes on HDMI

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_hdmi.c

@@ -1228,6 +1228,7 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
 
 	connector->interlace_allowed = 1;
 	connector->doublescan_allowed = 0;
+	connector->stereo_allowed = 1;
 
 	switch (port) {
 	case PORT_B: