IB/hfi1: Use kcalloc() in hfi1_user_exp_rcv_init()

* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus reuse the corresponding function "kcalloc".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data type by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hfi1/user_exp_rcv.c

@@ -200,8 +200,9 @@ int hfi1_user_exp_rcv_init(struct file *fp)
 
 	if (!HFI1_CAP_UGET_MASK(uctxt->flags, TID_UNMAP)) {
 		fd->invalid_tid_idx = 0;
-		fd->invalid_tids = kzalloc(uctxt->expected_count *
-					   sizeof(u32), GFP_KERNEL);
+		fd->invalid_tids = kcalloc(uctxt->expected_count,
+					   sizeof(*fd->invalid_tids),
+					   GFP_KERNEL);
 		if (!fd->invalid_tids) {
 			ret = -ENOMEM;
 			goto done;