IB/hfi1: Coding style improvement (make sizeof use safer)

Replace the specification of a data structure by a reference to
the desired member as the parameter for the operator "sizeof" 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_sdma.c

@@ -705,7 +705,9 @@ int hfi1_user_sdma_process_request(struct file *fp, struct iovec *iovec,
 	/* Save all the IO vector structures */
 	for (i = 0; i < req->data_iovs; i++) {
 		INIT_LIST_HEAD(&req->iovs[i].list);
-		memcpy(&req->iovs[i].iov, iovec + idx++, sizeof(struct iovec));
+		memcpy(&req->iovs[i].iov,
+		       iovec + idx++,
+		       sizeof(req->iovs[i].iov));
 		ret = pin_vector_pages(req, &req->iovs[i]);
 		if (ret) {
 			req->status = ret;