MAINTAINERS: Update maintainers of HiSilicon RoCE

Wenpeng has moved to other technical areas, and Junxian will
take over his responsibilities in maintaining this module.

Link: https://lore.kernel.org/r/20230506070604.2982542-1-xuhaoyue1@hisilicon.com


Signed-off-by: Haoyue Xu <xuhaoyue1@hisilicon.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>