iommu/vt-d: Use try_cmpxchg64() in intel_pasid_get_entry()

Use try_cmpxchg64() instead of cmpxchg64 (*ptr, old, new) != old in
intel_pasid_get_entry().  cmpxchg returns success in ZF flag, so
this change saves a compare after cmpxchg (and related move
instruction in front of cmpxchg).

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Will Deacon <will@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20240522082729.971123-2-ubizjak@gmail.com


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