dt-bindings: phy: Add qcom,snps-eusb2-repeater schema file

The SM8550 SoC uses Synopsis eUSB2 repeater found in PM8550b.
Add a dt-binding schema for the new driver.
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230208190200.2966723-2-abel.vesa@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/phy/qcom,snps-eusb2-repeater.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/qcom,snps-eusb2-repeater.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Synopsis eUSB2 to USB 2.0 repeater
+
+maintainers:
+  - Abel Vesa <abel.vesa@linaro.org>
+
+description:
+  eUSB2 repeater converts between eUSB2 and USB 2.0 signaling levels and
+  allows a eUSB2 PHY to connect to legacy USB 2.0 products
+
+properties:
+  compatible:
+    const: qcom,pm8550b-eusb2-repeater
+
+  reg:
+    maxItems: 1
+
+  "#phy-cells":
+    const: 0
+
+  vdd18-supply: true
+
+  vdd3-supply: true
+
+required:
+  - compatible
+  - reg
+  - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/spmi/spmi.h>
+
+    pmic@7 {
+      reg = <0x7 SPMI_USID>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      pm8550b_eusb2_repeater: phy@fd00 {
+        compatible = "qcom,pm8550b-eusb2-repeater";
+        reg = <0xfd00>;
+        #phy-cells = <0>;
+      };
+    };
+...