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

mainline inclusion
from mainline-v5.9-rc4
commit 26e495f3
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7R8MI
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=26e495f341075c09023ba16dee9a7f37a021e745

--------------------------------

mainline inclusion
from mainline-v5.9-rc4
commit 26e495f3
category: bugfix
bugzilla: 189075
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=26e495f341075c09023ba16dee9a7f37a021e745



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

Fixes: b9fc6b56 ("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: Guo Mengqi <guomengqi3@huawei.com>