pinctrl: renesas: r8a779f0: Add PCIe pins, groups, and function

Add pins, groups, and function for the PCIe Controllers 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/b2f95db490d13e8cb7d97a63d58d47933317e28a.1645457792.git.geert+renesas@glider.be