arm64: dts: broadcom: align pl330 node name with dtschema

Fixes dtbs_check warnings like:

  dma@310000: $nodename:0: 'dma@310000' does not match '^dma-controller(@.*)?$'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>