Update misleading comment in cifs_chan_update_iface

Since commit 8da33fd ("cifs: avoid deadlocks while updating iface")
cifs_chan_update_iface now takes the chan_lock itself, so update the
comment accordingly.

Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/smb/client/sess.c

@@ -347,10 +347,7 @@ cifs_disable_secondary_channels(struct cifs_ses *ses)
 	spin_unlock(&ses->chan_lock);
 }
 
-/*
- * update the iface for the channel if necessary.
- * Must be called with chan_lock held.
- */
+/* update the iface for the channel if necessary. */
 void
 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 {