pinctrl: sh-pfc: r8a77990: Add SCIF pins, groups and functions

This patch adds SCIF{0,1,2,3,4,5} pins, groups and functions to R8A77990
SoC.

Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>