staging/rdma/hfi1: Fix a possible null pointer dereference

A code inspection pointed out that kmalloc_array may return NULL and
memset doesn't check the input pointer for NULL, resulting in a possible
NULL dereference. This patch fixes this.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rdma/hfi1/chip.c

@@ -13358,6 +13358,8 @@ static void init_qos(struct hfi1_devdata *dd, u32 first_ctxt)
 	if (num_vls * qpns_per_vl > dd->chip_rcv_contexts)
 		goto bail;
 	rsmmap = kmalloc_array(NUM_MAP_REGS, sizeof(u64), GFP_KERNEL);
+	if (!rsmmap)
+		goto bail;
 	memset(rsmmap, rxcontext, NUM_MAP_REGS * sizeof(u64));
 	/* init the local copy of the table */
 	for (i = 0, ctxt = first_ctxt; i < num_vls; i++) {