dt-binding: ptp: fsl,ptp: add pci1957,ee02 compatible string for fsl,enetc-ptp

fsl,enetc-ptp is embedded pcie device. Add compatible string pci1957,ee02.

Fix warning:
arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-kbox-a-230-ls.dtb: ethernet@0,4:
compatible:0: 'pci1957,ee02' is not one of ['fsl,etsec-ptp', 'fsl,fman-ptp-timer', 'fsl,dpaa2-ptp', 'fsl,enetc-ptp']

Signed-off-by: Frank Li <[e-mail]>
Acked-by: Rob Herring (Arm) <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/devicetree/bindings/ptp/fsl,ptp.yaml

···
 
 properties:
   compatible:
-    enum:
-      - fsl,etsec-ptp
-      - fsl,fman-ptp-timer
-      - fsl,dpaa2-ptp
-      - fsl,enetc-ptp
+    oneOf:
+      - enum:
+          - fsl,etsec-ptp
+          - fsl,fman-ptp-timer
+          - fsl,dpaa2-ptp
+      - items:
+          - const: pci1957,ee02
+          - const: fsl,enetc-ptp
 
   reg:
     maxItems: 1
···
 required:
   - compatible
   - reg
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: fsl,enetc-ptp
+    then:
+      $ref: /schemas/pci/pci-device.yaml
 
 additionalProperties: false