of: Introduce of_translate_dma_region()

This function is similar to of_translate_dma_address() but also reads a
length in addition to an address from a device tree property.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20230120174251.4004100-2-thierry.reding@gmail.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>