RDMA: Use u64_to_user_ptr everywhere

This is already used in many places, get the rest of them too, only
to make the code a bit clearer & simpler.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/qib/qib_diag.c

@@ -614,7 +614,7 @@ static ssize_t qib_diagpkt_write(struct file *fp,
 	}
 
 	if (copy_from_user(tmpbuf,
-			   (const void __user *) (unsigned long) dp.data,
+			   u64_to_user_ptr(dp.data),
 			   dp.len)) {
 		ret = -EFAULT;
 		goto bail;