iommu/vt-d: Refactor IOTLB and Dev-IOTLB flush for batching

Extracts IOTLB and Dev-IOTLB invalidation logic from cache tag flush
interfaces into dedicated helper functions. It prepares the codebase
for upcoming changes to support batched cache invalidations.

To enable direct use of qi_flush helpers in the new functions,
iommu->flush.flush_iotlb and quirk_extra_dev_tlb_flush() are opened up.

No functional changes are intended.

Co-developed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20240815065221.50328-3-tina.zhang@intel.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>