dt-bindings: PCI: pci-ep: Add binding to specify virtual function

Add binding to specify virtual function (associated with each physical
function) in endpoint mode.

Link: https://lore.kernel.org/r/20210819123343.1951-2-kishon@ti.comSigned-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>

Documentation/devicetree/bindings/pci/pci-ep.yaml

@@ -23,6 +23,13 @@ properties:
     default: 1
     maximum: 255
 
+  max-virtual-functions:
+    description: Array representing the number of virtual functions corresponding to each physical
+      function
+    $ref: /schemas/types.yaml#/definitions/uint8-array
+    minItems: 1
+    maxItems: 255
+
   max-link-speed:
     $ref: /schemas/types.yaml#/definitions/uint32
     enum: [ 1, 2, 3, 4 ]