ARM: bcm: Use of_address_to_resource()

Replace open coded parsing of "reg" with of_address_to_resource().

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230319163125.224833-1-robh@kernel.org


Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>