iommu: msm: Use ion_phys_addr_t for iova argument

IOMMU mapping function is using the wrong type for its
IO Virtual Address (IOVA) causing the returned address
to contain garbage in the upper 32 bits when LPAE is enabled.

CRs-fixed: 564365
Change-Id: Ied592fe855a145b0ff32d2a6228ecfcf7fd0a53e
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>