dt-bindings: net: qcom,ipa: do not override firmware-name $ref

dtschema package defines firmware-name as string-array, so individual
bindings should not make it a string but instead just narrow the number
of expected firmware file names.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20240129142121.102450-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Documentation/devicetree/bindings/net/qcom,ipa.yaml

@@ -159,7 +159,7 @@ properties:
       when the AP (not the modem) performs early initialization.
 
   firmware-name:
-    $ref: /schemas/types.yaml#/definitions/string
+    maxItems: 1
     description:
       If present, name (or relative path) of the file within the
       firmware search path containing the firmware image used when