pmdomain: renesas: rcar-sysc: Absorb rcar_sysc_ch into rcar_sysc_pd

Until commit 7e8a50df ("soc: renesas: rcar-sysc: Drop legacy
handling") in v4.19, the rcar_sysc_ch structure was part of the API for
legacy board code not yet using DT.  Since then, there is no longer a
reason to keep it as a separate structure.

Moreover, a future quirk handling will need access to the rcar_sysc_pd
structure's flags member in rcar_sysc_pwr_on_off().  Hence absorb the
rcar_sysc_ch structure into the rcar_sysc_pd structure, and pass around
the latter instead of the former.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/672805a8c52ce63200e342212bbe6f84a445397b.1713348705.git.geert+renesas@glider.be


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>