pinctrl: renesas: r8a779f0: Add HSCIF pins, groups, and functions

Add pins, groups, and functions for the High Speed Serial Communication
Interfaces with FIFO (HSCIF) on the Renesas R-Car S4-8 (R8A779F0) SoC.

Based on a larger patch in the BSP by LUU HOAI.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/2b85b8857c1189fa6ee33e2f57fe746d740481d1.1645457792.git.geert+renesas@glider.be