clk: renesas: Add support for RZ/G2UL SoC

clk: renesas: Add support for RZ/G2UL SoC

The clock structure for RZ/G2UL is almost identical to RZ/G2L SoC with
fewer IP blocks. The IP blocks such as WDT1, GPT, H264, GPU and POEG are
not present on RZ/G2UL.

This patch adds minimal clock and reset entries required to boot the
system on Renesas RZ/G2UL SMARC EVK and binds it with the RZ/G2L CPG core
driver.

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/20220412161314.13800-2-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>