scripts/get_maintainers.pl: Don't blindly drop "THE REST" maintainers

scripts/get_maintainers.pl: Don't blindly drop "THE REST" maintainers

"THE REST" maintainers should always be CCed for any modification that
don't fall under the responsability of a specific component maintainer.

However, the script get_maintainers.pl will remove "THE REST"
maintainers as soon as one maintainer of a specific component will be
present.

Fix the script once for all.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>