dwc3-msm: Use upstream IOMMU driver based dma_ops() with USB dev

MSM specific IOMMU driver has below limitations:
(a) dma_map_sg() API doesn't support unaligned buffer usage.
(b) It doesn't perform cache flush.
Some of USB usecase (e.g. host mode mass storage case) uses unaligned
buffer with dma_map_sg() API which fails due to above (a) limitation.
Upstream IOMMU driver doesn't have above limitation. Hence to allow
USB SMMU stage S1 functionality use UPSTREAM_IOVA_ALLOCATOR attribute
which sets upstream IOMMU driver's dma_ops() with dev.

Change-Id: I0fd8c1eb38d0db454009d44b86e6d68be9304058
Signed-off-by: Mayank Rana <mrana@codeaurora.org>