arm64: dts: renesas: beacon: Fix audio-1.8V pin enable

The fact the audio worked at all was a coincidence because the wrong
gpio enable was used.  Use the correct GPIO pin to ensure its operation.

Fixes: a1d8a344 ("arm64: dts: renesas: Introduce r8a774a1-beacon-rzg2m-kit")
Signed-off-by: Adam Ford <aford173@gmail.com>
Link: https://lore.kernel.org/r/20201213183759.223246-6-aford173@gmail.com


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