iommu/vt-d: Remove users from intel_svm_dev

iommu/vt-d: Remove users from intel_svm_dev

It was used as a reference counter of an existing bond between device
and user application memory address. Commit be51b1d6bbff ("iommu/sva:
Refactoring iommu_sva_bind/unbind_device()") has added this in iommu
core. Remove it to avoid duplicate code.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230109014955.147068-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>