iommu/vt-d: Fix buggy QAT device mask

Impacted QAT device IDs that need extra dtlb flush quirk is ranging
from 0x4940 to 0x4943. After bitwise AND device ID with 0xfffc the
result should be 0x4940 instead of 0x494c to identify these devices.

Fixes: e65a6897

 ("iommu/vt-d: Add a fix for devices need extra dtlb flush")
Reported-by: Raghunathan Srinivasan <raghunathan.srinivasan@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Link: https://lore.kernel.org/r/20221203005610.2927487-1-jacob.jun.pan@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>