dt-bindings: imx6q-pcie: Restruct reg and reg-name

snps,dw-pcie.yaml already have reg and reg-name information, there is
no need to duplicate it here.

Add 'if' check for existing compatible string to restrict reg and reg-names,
in preparation for adding a add new compatible string with difference reg-names
sets.

Link: https://lore.kernel.org/r/20240220161924.3871774-9-Frank.Li@nxp.com
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml

@@ -30,16 +30,6 @@ properties:
       - fsl,imx8mm-pcie
       - fsl,imx8mp-pcie
 
-  reg:
-    items:
-      - description: Data Bus Interface (DBI) registers.
-      - description: PCIe configuration space region.
-
-  reg-names:
-    items:
-      - const: dbi
-      - const: config
-
   clocks:
     minItems: 3
     items:
@@ -90,6 +80,26 @@ required:
 allOf:
   - $ref: /schemas/pci/snps,dw-pcie.yaml#
   - $ref: /schemas/pci/fsl,imx6q-pcie-common.yaml#
+  - if:
+      properties:
+        compatible:
+          enum:
+            - fsl,imx6q-pcie
+            - fsl,imx6sx-pcie
+            - fsl,imx6qp-pcie
+            - fsl,imx7d-pcie
+            - fsl,imx8mq-pcie
+            - fsl,imx8mm-pcie
+            - fsl,imx8mp-pcie
+    then:
+      properties:
+        reg:
+          maxItems: 2
+        reg-names:
+          items:
+            - const: dbi
+            - const: config
+
   - if:
       properties:
         compatible: