RDMA/hns: Replace get_udp_sport with rdma_get_udp_sport

Several drivers have the same function xxx_get_udp_sport. So this
function is moved to ib_verbs.h.

Link: https://lore.kernel.org/r/20220106180359.2915060-3-yanjun.zhu@linux.dev


Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>