iommu/arm-smmu: configure stream IDs for PCI-e devices dynamically

PCI-e devices on MSM systems need to have their stream IDs configured at
device add time, since they're not known at system design time and
therefore can't be placed in the device tree.  Add the necessary calls
into the MSM PCI-e driver to obtain stream IDs for devices behind PCI-e
at device add time.

Change-Id: I3645a525c3ab5ef6d89eeaa99894542bd3aa261f
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>