iommu/arm-smmu-v3: Update comment about STE liveness

Update the comment to reflect the fact that the STE is not always
installed. arm_smmu_domain_finalise_s1 intentionnaly calls
arm_smmu_write_ctx_desc while the STE is not installed.

Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Michael Shavit <mshavit@google.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/20230915211705.v8.8.I7a8beb615e2520ad395d96df94b9ab9708ee0d9c@changeid
Signed-off-by: Will Deacon <will@kernel.org>

Author: shavitmichael

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

@@ -1091,7 +1091,7 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_master *master, int ssid,
 		cdptr[3] = cpu_to_le64(cd->mair);
 
 		/*
-		 * STE is live, and the SMMU might read dwords of this CD in any
+		 * STE may be live, and the SMMU might read dwords of this CD in any
 		 * order. Ensure that it observes valid values before reading
 		 * V=1.
 		 */