drm: Drop drm_get_link_status_name()

drm_get_link_status_name() isn't used so kill it.

Fixes the following sparse warning:
drm_connector.c:618:1: warning: symbol 'drm_get_link_status_name' was not declared. Should it be static?

Cc: Manasi Navare <manasi.d.navare@intel.com>
Fixes: 40ee6fbef75f ("drm: Add a new connector atomic property for link status")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170901165328.24459-3-ville.syrjala@linux.intel.com
Reviewed-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/drm_connector.c

@@ -615,7 +615,6 @@ static const struct drm_prop_enum_list drm_link_status_enum_list[] = {
 	{ DRM_MODE_LINK_STATUS_GOOD, "Good" },
 	{ DRM_MODE_LINK_STATUS_BAD, "Bad" },
 };
-DRM_ENUM_NAME_FN(drm_get_link_status_name, drm_link_status_enum_list)
 
 /**
  * drm_display_info_set_bus_formats - set the supported bus formats