MAINTAINERS: Remove Mitesh Ahuja from emulex maintainers

Remove Mitesh Ahuja <mitesh.ahuja@avagotech.com> from
maintainers file. This email address seems not active
and causes to mail bounces during submissions.

Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>