[IPoIB] cleanups: fix comment, remove useless variables

Minor cleanups: fix a misleading comment, and get rid of attr_mask
variables that are only used to hold constants (just use the constants
directly).

Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
index b5902a7..e829e10 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
@@ -41,7 +41,6 @@
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ib_qp_attr *qp_attr;
-	int attr_mask;
 	int ret;
 	u16 pkey_index;
 
@@ -59,8 +58,7 @@
 
 	/* set correct QKey for QP */
 	qp_attr->qkey = priv->qkey;
-	attr_mask = IB_QP_QKEY;
-	ret = ib_modify_qp(priv->qp, qp_attr, attr_mask);
+	ret = ib_modify_qp(priv->qp, qp_attr, IB_QP_QKEY);
 	if (ret) {
 		ipoib_warn(priv, "failed to modify QP, ret = %d\n", ret);
 		goto out;