dt-bindings: PCI: fsl,imx6q-pcie: Add optional DMA interrupt

The i.MX8QM and i.MX8QXP/DXP have an additional interrupt for DMA.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250225102726.654070-2-alexander.stein@ew.tq-group.com
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>

Author: tq-steina

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

@@ -47,12 +47,16 @@ properties:
     maxItems: 5
 
   interrupts:
+    minItems: 1
     items:
       - description: builtin MSI controller.
+      - description: builtin DMA controller.
 
   interrupt-names:
+    minItems: 1
     items:
       - const: msi
+      - const: dma
 
   reset-gpio:
     description: Should specify the GPIO for controlling the PCI bus device