arm64: dts: allwinner: a64: bananapi-m64: Enable audio codec

This patch enables audio via the SoC's internal audio codec. All
relevant device nodes are enabled, and the routing is set to match
the board design. MIC1 is routed to an onboard microphone, with MBIAS
providing power. MIC2 and HP are routed to the 3.5mm headset TRRS jack.
No phantom power is provided to the headset microphone.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>