RDMA/hns: Replace custom macros HNS_ROCE_ALIGN_UP

HNS_ROCE_ALIGN_UP can be replaced by round_up() which is defined in
kernel.h.

Link: https://lore.kernel.org/r/1578313276-29080-7-git-send-email-liweihang@huawei.com


Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>