vfio/pci: Register and allow DMA FAULT IRQ signaling

virt inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I401IF


CVE: NA

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Register the VFIO_IRQ_TYPE_NESTED/VFIO_IRQ_SUBTYPE_DMA_FAULT
IRQ that allows to signal a nested mode DMA fault.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Kunkun <Jiang&lt;jiangkunkun@huawei.com>
Reviewed-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>