cxgb4: fix memory leak during module unload

Fix the memory leak in mps during module unload
path by freeing mps reference entries if the list
adpter->mps_ref is not already empty

Fixes: 28b3870 ("cxgb4: Re-work the logic for mps refcounting")
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_mps.c

@@ -229,7 +229,7 @@ void cxgb4_free_mps_ref_entries(struct adapter *adap)
 {
 	struct mps_entries_ref *mps_entry, *tmp;
 
-	if (!list_empty(&adap->mps_ref))
+	if (list_empty(&adap->mps_ref))
 		return;
 
 	spin_lock(&adap->mps_ref_lock);