MAINTAINERS: Change drew's email address

As a side effect of leaving Red Hat I won't be able to use my Red Hat
email address anymore. I'm also changing the name of my gitlab group.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Thomas Huth <thuth@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Andrew Jones <drjones@redhat.com>