KVM: fix irqfd error checking

Michael Tsirkin pointed out that f_ops->poll() does not return a standard
"int" error, yet we are treating it as such. Lets fix this.

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
1 file changed