iommu/vt-d: Enable QI on all IOMMUs before setting root entry

This seems to be required on some X58 chipsets on systems
with more than one IOMMU. QI does not work until it is
enabled on all IOMMUs in the system.

Reported-by: Dheeraj CVR <cvr.dheeraj@gmail.com>
Tested-by: Dheeraj CVR <cvr.dheeraj@gmail.com>
Fixes: 5f0a7f76 ('iommu/vt-d: Make root entry visible for hardware right after allocation')
Cc: stable@vger.kernel.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>