I'm moving my git repositories to gitlab.com, update MAINTAINERS
to point to the correct URL.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20201214212032.2999853-1-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>