msm: ipa: use IOMMU_MMIO only for device type

Remove IOMMU_MMIO flag from all the DDR mappings
done by IPA.

Change-Id: I8147d3ded0dbd71b87f2e8a8bc05531e19164a83
CRs-Fixed: 2254877
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>