pinctrl: sh-pfc: r8a77995: Add VIN4 pins, groups and function

This patch adds VIN4 pins, groups and function for the
R8A77995 (D3) SoC.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>