of: unittest: Add bus address range parsing tests

of: unittest: Add bus address range parsing tests

[ Upstream commit 6d32dadb11a6480be62c6ada901bbdcbda1775c9 ]

While there are tests for "dma-ranges" helpers, "ranges" is missing any
tests. It's the same underlying code, but for completeness add a test
for "ranges" parsing iterators. This is in preparation to add some
additional "ranges" helpers.

Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-1-e2456c3e77ab@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Stable-dep-of: 7f05e20b989a ("of: address: Preserve the flags portion on 1:1 dma-ranges mapping")
Signed-off-by: Sasha Levin <sashal@kernel.org>