boards: renesas: Add minimal support for board RSK+ for RZ/N2L

Add minimal support for board RSK+ for RZ/N2L

Signed-off-by: Nhut Nguyen <nhut.nguyen.kc@renesas.com>
Signed-off-by: Hoang Nguyen <hoang.nguyen.jx@bp.renesas.com>
9 files changed