pinctrl: sh-pfc: r8a7795: Fix to delete A20..A25 pins function definitions

This patch fixes the macro definitions of A20..A25 pins function deleted.

This is a correction because IPSR register specification for R8A7795 ES2.0
SoC was changed in R-Car Gen3 Hardware User's Manual Rev.0.53E.

Fixes: b205914c ("pinctrl: sh-pfc: r8a7795: Add support for R-Car H3 ES2.0")
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>