arm64: dts: renesas: r9a07g044: Add SSI support

Add SSI{0,1,2,3} nodes to RZ/G2L SoC DTSI.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20210814135526.15561-3-biju.das.jz@bp.renesas.com


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