qemu: Fix memory (and FD) leak on PCI device detach
qemu: Fix memory (and FD) leak on PCI device detach

https://bugzilla.redhat.com/show_bug.cgi?id=877095

Unmanaged PCI devices were only leaked if pciDeviceListAdd failed but
managed devices were always leaked. And leaking PCI device is likely to
leave PCI config file descriptor open. This patch fixes
qemuReattachPciDevice to either free the PCI device or add it to the
inactivePciHostdevs list.
(cherry picked from commit 6910318798d9dda9c20732bb7f7aba90e7871737)

mithleshvrts/libvirt-0.10.2,mithleshvrts/libvirt-0.10.2,mithleshvrts/libvirt-0.10.2,mithleshvrts/libvirt-0.10.2,mithleshvrts/libvirt-0.10.2