uwb: remove unused beacon group join/leave events

The UWB_NOTIF_BG_JOIN/UWB_NOTIF_BG_LEAVE events have been
superceeded by the channel_changed callback in struct uwb_pal.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
diff --git a/drivers/uwb/beacon.c b/drivers/uwb/beacon.c
index 2479560..d9c60cb 100644
--- a/drivers/uwb/beacon.c
+++ b/drivers/uwb/beacon.c
@@ -140,10 +140,8 @@
 		}
 	}
 
-	if (result >= 0) {
+	if (result >= 0)
 		rc->beaconing = channel;
-		uwb_notify(rc, NULL, uwb_bg_joined(rc) ? UWB_NOTIF_BG_JOIN : UWB_NOTIF_BG_LEAVE);
-	}
 	return result;
 }
 
@@ -581,19 +579,6 @@
 	return result;
 }
 
-/**
- * uwb_bg_joined - is the RC in a beacon group?
- * @rc: the radio controller
- *
- * Returns true if the radio controller is in a beacon group (even if
- * it's the sole member).
- */
-int uwb_bg_joined(struct uwb_rc *rc)
-{
-	return rc->beaconing != -1;
-}
-EXPORT_SYMBOL_GPL(uwb_bg_joined);
-
 /*
  * Print beaconing state.
  */