The current memory region assign only supports a single
memory region.

But new platforms introduces more regions to make the
memory requirements more flexible for various use cases.
Those new platforms also shares the memory region between the
DSP and HLOS.

To handle this, make the region assign more generic in order
to support more than a single memory region and also permit
setting the regions permissions as shared.
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20240123-topic-sm8650-upstream-remoteproc-v7-2-61283f50162f@linaro.orgSigned-off-by: Bjorn Andersson <andersson@kernel.org>