Add the module clock used by the Pin Function (PFC/GPIO) controller
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/4ef3d3dfe714ad75112e4886efea0b66e40a33bc.1645457502.git.geert+renesas@glider.be