Currently, the pages that are allocated for the single mode of MSC are not
mapped into the device's dma space and the code is incorrectly using
*_to_phys() in place of a dma address. This fails with IOMMU enabled and
is otherwise bad practice.

Fix the single mode buffer allocation to map the pages into the device's
DMA space.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: ba82664c ("intel_th: Add Memory Storage Unit driver")
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>