dt-bindings: usb: qcom,dwc3: Add QCS615 to USB DWC3 bindings

Update dt-bindings to add primary controller of QCS615 to USB
DWC3 controller list.

Although this controller has a QUSB2 Phy, it belongs to a
generation of SoCs like SDM670/SDM845/SM6350 where DP/DM is
used for wakeup instead of qusb2_phy interrupt.

Signed-off-by: Krishna Kurapati <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/usb/qcom,dwc3.yaml

···
           - qcom,msm8998-dwc3
           - qcom,qcm2290-dwc3
           - qcom,qcs404-dwc3
+          - qcom,qcs615-dwc3
           - qcom,qcs8300-dwc3
           - qcom,qdu1000-dwc3
           - qcom,sa8775p-dwc3
···
           contains:
             enum:
               - qcom,qcm2290-dwc3
+              - qcom,qcs615-dwc3
               - qcom,sar2130p-dwc3
               - qcom,sc8180x-dwc3
               - qcom,sc8180x-dwc3-mp
···
               - qcom,ipq4019-dwc3
               - qcom,ipq8064-dwc3
               - qcom,msm8994-dwc3
+              - qcom,qcs615-dwc3
               - qcom,qcs8300-dwc3
               - qcom,qdu1000-dwc3
               - qcom,sa8775p-dwc3