vfio/pci: Disable INTx in vfio_realize error path

vfio/pci: Disable INTx in vfio_realize error path

When vfio realize fails, INTx isn't disabled if it has been enabled.
This may confuse host side with unhandled interrupt report.

Fixes: c5478fea27ac ("vfio/pci: Respond to KVM irqchip change notifier")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
(cherry picked from commit adee0da0368f50b3ee934cdeeb6076466dabb268)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>