mac80211: use sdata mesh_id_len instead of wdev's

Since we copy the mesh_id_len into our own data structures,
use it consistently and don't sometimes use cfg80211's copy.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mesh.c

diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index b02ac33..836ec01 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -1216,7 +1216,7 @@
 	sdata_lock(sdata);
 
 	/* mesh already went down */
-	if (!sdata->wdev.mesh_id_len)
+	if (!sdata->u.mesh.mesh_id_len)
 		goto out;
 
 	rx_status = IEEE80211_SKB_RXCB(skb);
@@ -1269,7 +1269,7 @@
 	sdata_lock(sdata);
 
 	/* mesh already went down */
-	if (!sdata->wdev.mesh_id_len)
+	if (!sdata->u.mesh.mesh_id_len)
 		goto out;
 
 	if (ifmsh->preq_queue_len &&