soc: renesas: Kconfig: Enable SoCs by default when ARCH_RENESAS is set

Enable various Renesas SoCs by default when ARCH_RENESAS is selected.
Adding default y if ARCH_RENESAS to the relevant configurations removes
the need to manually enable individual SoCs in defconfig files.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/20250401090133.68146-2-prabhakar.mahadev-lad.rj@bp.renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>