iommu: msm: validate subsequent lazy map arguments

Validate that attempts to lazy map a buffer, that is already
lazy mapped, request the same number of elements, direction
and dma mapping attributes as the original mapping.

Change-Id: I6094cd6281a22525aa9971f1c5684f423be08580
Signed-off-by: Liam Mark <lmark@codeaurora.org>