iommu/amd: Restore IRTE.RemapEn bit after programming IRTE

iommu/amd: Restore IRTE.RemapEn bit after programming IRTE

BugLink: https://bugs.launchpad.net/bugs/1895880
[ Upstream commit 26e495f341075c09023ba16dee9a7f37a021e745 ]

Currently, the RemapEn (valid) bit is accidentally cleared when
programming IRTE w/ guestMode=0. It should be restored to
the prior state.

Fixes: b9fc6b56f478 ("iommu/amd: Implements irq_set_vcpu_affinity() hook to setup vapic mode for pass-through devices")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20200903093822.52012-2-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: William Breathitt Gray <william.gray@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>