arm64: dts: qcom: sm6350: Add q6usbdai node

arm64: dts: qcom: sm6350: Add q6usbdai node

Add a node for q6usb which handles USB audio offloading, allowing to
play audio via a USB-C headset with lower power consumption and enabling
some other features.

We also need to set num-hc-interrupters for the dwc3 for the q6usb to be
able to use its sideband interrupter.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250501-fp4-usb-audio-offload-v2-4-30f4596281cd@fairphone.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>