msm: smmu: add re-route calling for specified iova.

When calling smmu mapping, if iova is specified directly by user, not
allocated dynamically in dma-mapping.c, smmu driver needs to provide
support for this. This is needed in early display case. In this scenario,
LK has set physical memory to display hardware for fetching, so if iova
is not explicitly specified in kernel, but instead dynamically produced
by "alloc_iova" in dma-mapping.c, display hardware has no chance to know
this new iova, then smmu fault will happen if enabling the iommu stage-1
translation.
To fix this smmu fault problem, add re-routing to the right path when
iova specified by user is not 0 in smmu map/unmap function.

Change-Id: I062b04d7eec65af1c106a5caa09ec787b5d26d0d
Signed-off-by: Guchun Chen <guchunc@codeaurora.org>