arm: dma-mapping: Add APIs for other memory types

Currently, the only attributes supported for DMA memory are
writecombine and coherent. Both of these allow speculative
prefetches to occur. For certain use cases (e.g. content
protection) there are requirements to disallow prefetching.
Relatedly, there may be cases where buffering is not enough
for high performance use cases and the full cache should
be used. Add appropriate APIs for the strongly ordered and
cached memory types for the needed use cases.

Change-Id: Ibe17b3d002f9615e2cb34183f47f6d1bcd045611
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>