dt-bindings: usb: Introduce qcom,snps-dwc3

The Qualcomm USB glue is not separate of the Synopsys DWC3 core and
several of the snps,dwc3 properties (such as clocks and reset) conflicts
in expectation with the Qualcomm integration.

Using the newly split out Synopsys DWC3 core properties, describe the
Qualcomm USB block in a single block. The new binding is a copy of
qcom,dwc3 with the needed modifications.

It would have been convenient to retain the two structures with the same
compatibles, but as there exist no way to select a binding based on the
absence of a subnode/patternProperty, a new generic compatible is
introduced to describe this binding.

To avoid redefining all the platform-specific compatibles, "select" is
used to tell the DeviceTree validator which binding to use solely on the
generic compatible. (Otherwise if the specific compatible matches during
validation, the generic one must match as well)

Mark qcom,dwc3 deprecated, to favor expressing future platforms using
the new combined binding.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-QRD
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250414-dwc3-refactor-v7-2-f015b358722d@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

@@ -4,11 +4,22 @@
 $id: http://devicetree.org/schemas/usb/qcom,dwc3.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: Qualcomm SuperSpeed DWC3 USB SoC controller
+title: Legacy Qualcomm SuperSpeed DWC3 USB SoC controller
 
 maintainers:
   - Wesley Cheng <quic_wcheng@quicinc.com>
 
+# Use the combined qcom,snps-dwc3 instead
+deprecated: true
+
+select:
+  properties:
+    compatible:
+      contains:
+        const: qcom,dwc3
+  required:
+    - compatible
+
 properties:
   compatible:
     items: