arm64: dts: renesas: falcon-csi-dsi: Add GPIO extenders

We need to configure their GPIOs to power on the MAX96712s.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20210413181447.2588084-1-niklas.soderlund+renesas@ragnatech.se


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