phy: dt-bindings: Add Cadence D-PHY Rx bindings

The Rx mode DPHY is different from Tx mode DPHY. Add a separate binding
for it.

Signed-off-by: Pratyush Yadav <[e-mail]>
Reviewed-by: Laurent Pinchart <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>

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

Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/cdns,dphy-rx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cadence DPHY Rx Device Tree Bindings
+
+maintainers:
+  - Pratyush Yadav <[e-mail]>
+
+properties:
+  compatible:
+    items:
+      - const: cdns,dphy-rx
+
+  reg:
+    maxItems: 1
+
+  "#phy-cells":
+    const: 0
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/soc/ti,sci_pm_domain.h>
+
+    dphy0: phy@4580000 {
+        compatible = "cdns,dphy-rx";
+        reg = <0x4580000 0x1100>;
+        #phy-cells = <0>;
+        power-domains = <&k3_pds 147 TI_SCI_PD_EXCLUSIVE>;
+    };