Remove Mike's contact from maintainers file.

Link: https://lore.kernel.org/r/20220329184221.182061.69846.stgit@awfm-01.cornelisnetworks.comSigned-off-by: NDennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>