clk: renesas: r8a779g0: Add PFC/GPIO clocks

Add the module clocks used by the Pin Function Controller (PFC) and
General Purpose Input/Output (GPIO) blocks on the Renesas R-Car V4H
(R8A779G0) SoC.

Extracted from a larger patch in the BSP by Kazuya Mizuguchi.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/cc6a22f0ad49643e17b9921b27aa9cf0a3b8d57a.1662714852.git.geert+renesas@glider.be