riscv: dts: starfive: visionfive 2: update sound and codec dt node name

Use "audio-codec" as the codec dt node name, and "sound" as the simple
audio card dt name.

Suggested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>