arm64: dts: renesas: r8a779f0: Add I2C nodes

Add device nodes for the I2C Bus Interfaces 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>
Link: https://lore.kernel.org/r/e1c7fb17801bc82a74aa5364212d02ba51535dd2.1643898884.git.geert+renesas@glider.be