boards: renesas: add support entropy using SCE9 for RA

Add support entropy driver for boards: ek_ra6m5, ek_ra6m4,
fpb_ra6e1, ek_ra4m3, ek_ra4m2

Signed-off-by: Danh Doan <danh.doan.ue@bp.renesas.com>
Signed-off-by: Khoa Nguyen <khoa.nguyen.xh@renesas.com>