OF: Retire dma-ranges mask workaround

The fixup adding 1 to the dma-ranges size may have been for the benefit
of some early AMD Seattle DTs, or may have merely been a just-in-case,
but either way anyone who might have deserved to get the message has
hopefully seen the warning in the 9 years we've had it there. The modern
dma_range_map mechanism should happily handle odd-sized ranges with no
ill effect, so there's little need to care anyway now. Clean it up.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/26620039901fdae52079ec1c8a4b2b324964a13e.1713523152.git.robin.murphy@arm.com


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