qemu: Refactor qemuDomainBlockJobAbort()
qemu: Refactor qemuDomainBlockJobAbort()

Change few variable names and refactor the code flow. As an additional
bonus the function now fails if the event state is not as expected.

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