clk: renesas: add R906G032 driver

Clock driver for the Renesas RZ/N1 SoC family. This is based on
Linux kernel 6.2.y drivers/clk/renesas/r9a06g032-clocks.c as found in
commit 02693e11611e ("clk: renesas: r9a06g032: Repair grave increment error"),
with the following additional patch series applied:
https://lore.kernel.org/linux-renesas-soc/20230301215520.828455-1-ralph.siemsen@linaro.org/



Notable difference: this version avoids allocating a 'struct clk'
for each clock source, as this is problematic before relocation.
Instead, it uses the same approach as existing Renesas R-Car Gen2/3
clock drivers, using a temporary structure filled on-the-fly.

Signed-off-by: Ralph Siemsen <ralph.siemsen@linaro.org>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>