cxgb4: Fix static checker warning

The patch e85c9a7a: ("cxgb4/cxgb4vf: Add code to calculate T5 BAR2
Offsets for SGE Queue Registers") from Dec 3, 2014, leads to the
following static checker warning:

        drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:5358
	t4_bar2_sge_qregs()
        warn: should '(qid >> qpp_shift) << page_shift' be a 64 bit type?

This patch fixes it
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/t4_hw.c

@@ -6053,7 +6053,7 @@ int t4_bar2_sge_qregs(struct adapter *adapter,
 	 *  o The BAR2 Queue ID.
 	 *  o The BAR2 Queue ID Offset into the BAR2 page.
 	 */
-	bar2_page_offset = ((qid >> qpp_shift) << page_shift);
+	bar2_page_offset = ((u64)(qid >> qpp_shift) << page_shift);
 	bar2_qid = qid & qpp_mask;
 	bar2_qid_offset = bar2_qid * SGE_UDB_SIZE;