pinctrl: renesas: r8a779g0: Add missing SCIF3

R-Car V4H has SCIF3 and SCIF3_A, but current PFC setting is mixed.
This patch cleans up SCIF3/SCIF3_A, based on Rev.0.51.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87v8shsja7.wl-kuninori.morimoto.gx@renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>