dt-bindings: dma: Increase iommu maxItems for BAM DMA

Since SM8250 BAM DMA engine supports six iommu entries,
increase the maxItems in the iommu property section, without
which 'dtbs_check' would throw errors.

Acked-by: Krzysztof Kozlowski <[e-mail]>
Tested-by: Anders Roxell <[e-mail]>
Tested-by: Linux Kernel Functional Testing <[e-mail]>
Signed-off-by: Bhupesh Sharma <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml

···
 
   iommus:
     minItems: 1
-    maxItems: 4
+    maxItems: 6
 
   num-channels:
     $ref: /schemas/types.yaml#/definitions/uint32