arm64: dts: qcom: msm8916: Declare sound node in msm8916.dtsi

arm64: dts: qcom: msm8916: Declare sound node in msm8916.dtsi

The "sound" node in apq8016-sbc.dtsi references memory regions
provided by the SoC and should be therefore declared in msm8916.dtsi.

Additionally, the machine driver used for the "qcom,apq8016-sbc-sndcard"
compatible also works on other MSM8916 devices (provided that audio
routing is set up properly). It is not really specific to apq8016-sbc.

Simplify setting up sound on other boards by moving the common part
to msm8916.dtsi. This also allows referencing the node by the label,
so that we can eventually drop the "soc" node entirely from the
board-specific device tree part and use labels exclusively.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20200720085406.6716-3-stephan@gerhold.net
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>