arm64: dts: juno: Drop useless 'dma-channels/requests' properties

The pl330 DMA controller provides number of DMA channels and requests
through its registers, so duplicating this information (with a chance of
mistakes) in DTS is pointless.  Additionally the DTS used always wrong
property names which causes DT schema check failures - the bindings
documented 'dma-channels' and 'dma-requests' properties without leading
hash sign.

Another reason is that the number of requests also does not seem right
(should be 8).

Link: https://lore.kernel.org/r/20220430121902.59895-5-krzysztof.kozlowski@linaro.org


Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>