iommu/amd: Fix interrupt remapping when disable guest_mode

iommu/amd: Fix interrupt remapping when disable guest_mode

Pass-through devices to VM guest can get updated IRQ affinity
information via irq_set_affinity() when not running in guest mode.
Currently, AMD IOMMU driver in GA mode ignores the updated information
if the pass-through device is setup to use vAPIC regardless of guest_mode.
This could cause invalid interrupt remapping.

Also, the guest_mode bit should be set and cleared only when
SVM updates posted-interrupt interrupt remapping information.

Signed-off-by: Suravee Suthikulpanit <[email protected]>
Cc: Joerg Roedel <[email protected]>
Fixes: d98de49a53e48 ('iommu/amd: Enable vAPIC interrupt remapping mode by default')
Signed-off-by: Joerg Roedel <[email protected]>