drivers: of: of_reserved_mem: fixup the CMA alignment not to affect dma-coherent

There was an alignment mismatch issue for CMA and it was fixed by
commit 1cc8e345 ("drivers: of: of_reserved_mem: fixup the alignment with CMA setup").
However the way of the commit considers not only dma-contiguous(CMA) but also
dma-coherent which has no that requirement.

This patch checks more to distinguish dma-contiguous(CMA) from dma-coherent.

Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Acked-by: Jason Liu <r64343@freescale.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
[robh: remove erroneous opening bracket]
Signed-off-by: Rob Herring <robh@kernel.org>