msm: Change vendor name from 'qcom' to 'qti' for iommu

As we have recently moved to use 'qti' as vendor name,
reflect that change for all the code related to iommu,
including version 0 and 1.

Change-Id: If67f2a778c64fc5c49f7b07e19ec31fb0cda8d52
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>