Add pins, groups, and function for the Clock-Synchronized Serial
Interfaces with FIFO (MSIOF) 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/c625769714b1027a756dd2ed4a017eb24708a041.1645457792.git.geert+renesas@glider.be