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

Extracted from 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/6369359a53483291ee536787c8a232462ff1b3a9.1645457792.git.geert+renesas@glider.be