PASID support and enable bit in the context entry isn't the right
indicator for the type of tables (legacy or scalable mode). Check
the DMA_RTADDR_SMT bit in the root context pointer instead.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Sai Praneeth <sai.praneeth.prakhya@intel.com>
Fixes: dd5142ca ("iommu/vt-d: Add debugfs support to show scalable mode DMAR table internals")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>