pinctrl: renesas: Drop support for Renesas-specific properties

The last user of the Renesas-specific properties was converted to the
standard properties in commit af897250 ("ARM: dts: gose: use
generic pinctrl properties in SDHI nodes") in v4.10.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/ff9c14781110bbf19b56b45dd1f01e6da90319ad.1678704441.git.geert+renesas@glider.be