hfi1: get rid of pointless access_ok()

pin_user_pages_fast() doesn't need that from its caller.
NB: only reachable from ->ioctl(), and only under USER_DS
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

drivers/infiniband/hw/hfi1/user_exp_rcv.c

@@ -206,13 +206,6 @@ static int pin_rcv_pages(struct hfi1_filedata *fd, struct tid_user_buf *tidbuf)
 		return -EINVAL;
 	}
 
-	/* Verify that access is OK for the user buffer */
-	if (!access_ok((void __user *)vaddr,
-		       npages * PAGE_SIZE)) {
-		dd_dev_err(dd, "Fail vaddr %p, %u pages, !access_ok\n",
-			   (void *)vaddr, npages);
-		return -EFAULT;
-	}
 	/* Allocate the array of struct page pointers needed for pinning */
 	pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
 	if (!pages)