We are now using the dts/upstream subtree for the RZ/G2L SoC family, so
update the board MAINTAINERS file to match rz-smarc dtsi files in this
subtree.
Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>