virtio_scsi: fix race on device removal
virtio_scsi: fix race on device removal

We cancel event work on device removal, but an interrupt
could trigger immediately after this, and queue it
again.

To fix, set a flag.

Loosely based on patch by Paolo Bonzini

Signed-off-by: Paolo Bonzini <69d3ebcf5ee4e7f05a50dc23cd96655b730804b4@redhat.com>
Signed-off-by: Michael S. Tsirkin <255103e50249e3d658441816e0597170ebfc16ef@redhat.com>
Signed-off-by: Rusty Russell <df9728c9e5104131c08c7adb03af425394842596@rustcorp.com.au>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs