drm/amd/display: Clear connector's edid pointer

Clear connector's edid pointer on coonnector update, when unplugging
the display.

Fix poison EDID when hotplugging on previously used connector.

Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -911,6 +911,7 @@ amdgpu_dm_update_connector_after_detect(struct amdgpu_dm_connector *aconnector)
 		drm_mode_connector_update_edid_property(connector, NULL);
 		aconnector->num_modes = 0;
 		aconnector->dc_sink = NULL;
+		aconnector->edid = NULL;
 	}
 
 	mutex_unlock(&dev->mode_config.mutex);