qemu: Use the hostdev alias in qemuDomainAttachHostSCSIDevice error path
qemu: Use the hostdev alias in qemuDomainAttachHostSCSIDevice error path

https://bugzilla.redhat.com/show_bug.cgi?id=1289391

Rather than pass the whole drive string (which contained the alias),
pass only the alias for the qemuMonitorDriveDel call in the error
path when adding a host device in the monitor fails.

olafhering/libvirt,taget/libvirt,jardasgit/libvirt,andreabolognani/libvirt,eskultety/libvirt,taget/libvirt,zippy2/libvirt,zippy2/libvirt,jardasgit/libvirt,libvirt/libvirt,libvirt/libvirt,andreabolognani/libvirt,eskultety/libvirt,jfehlig/libvirt,andreabolognani/libvirt,jfehlig/libvirt,eskultety/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,nertpinx/libvirt,jardasgit/libvirt,jardasgit/libvirt,datto/libvirt,olafhering/libvirt,libvirt/libvirt,datto/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,libvirt/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,taget/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,jardasgit/libvirt,zippy2/libvirt,taget/libvirt,datto/libvirt,fabianfreyer/libvirt,crobinso/libvirt,VenkatDatta/libvirt,VenkatDatta/libvirt,datto/libvirt,taget/libvirt,datto/libvirt,olafhering/libvirt,VenkatDatta/libvirt,eskultety/libvirt,olafhering/libvirt,eskultety/libvirt,crobinso/libvirt,zippy2/libvirt,crobinso/libvirt,nertpinx/libvirt,nertpinx/libvirt,crobinso/libvirt,nertpinx/libvirt,VenkatDatta/libvirt