dt-bindings: PCI: fsl,imx6q-pcie: Add missing type for 'reset-gpio-active-high'

'reset-gpio-active-high' is missing a type definition and is not a common
property. The type is boolean.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Richard Zhu <hongxing.zhu@nxp.com>
Link: https://lore.kernel.org/r/20220719215031.1875860-1-robh@kernel.org

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

@@ -144,6 +144,7 @@ properties:
     description: If present then the reset sequence using the GPIO
       specified in the "reset-gpio" property is reversed (H=reset state,
       L=operation state) (optional required).
+    type: boolean
 
   vpcie-supply:
     description: Should specify the regulator in charge of PCIe port power.