mac80211/mesh: make the preq queue lock consistent

Make mesh_preq_queue_lock locking consistent with mesh_queue_preq() using
spin_lock_bh().

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 3460108..8404fa5 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -792,9 +792,9 @@
 		return;
 	}
 
-	spin_lock(&ifmsh->mesh_preq_queue_lock);
+	spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
 	if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
-		spin_unlock(&ifmsh->mesh_preq_queue_lock);
+		spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
 		kfree(preq_node);
 		if (printk_ratelimit())
 			mhwmp_dbg("PREQ node queue full\n");
@@ -806,7 +806,7 @@
 
 	list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
 	++ifmsh->preq_queue_len;
-	spin_unlock(&ifmsh->mesh_preq_queue_lock);
+	spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
 
 	if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
 		ieee80211_queue_work(&sdata->local->hw, &sdata->work);