dt-bindings: usb: Clean-up "usb-phy" constraints

"usb-phy" has multiple type definitions. Unify the type with the looser
definition, phandle-array, as there are cases with multiple entries
(USB2 and USB3). However, the 'phandle-array' type alone is a bit
ambiguous. It can be either just an array of phandles or an array of
phandles plus args. "usb-phy" is the former and needs to constrain each
entry to a single phandle value.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20240124190725.1554080-1-robh@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml

@@ -313,7 +313,7 @@ properties:
 
   usb-phy:
     description: phandle for the PHY device. Use "phys" instead.
-    $ref: /schemas/types.yaml#/definitions/phandle
+    maxItems: 1
     deprecated: true
 
   fsl,usbphy:

Documentation/devicetree/bindings/usb/usb.yaml

@@ -25,6 +25,8 @@ properties:
 
   usb-phy:
     $ref: /schemas/types.yaml#/definitions/phandle-array
+    items:
+      maxItems: 1
     description:
       List of all the USB PHYs on this HCD to be accepted by the legacy USB
       Physical Layer subsystem.