qemu: monitor: Fix error message and comment when getting cpu info
qemu: monitor: Fix error message and comment when getting cpu info

In qemuMonitorJSONExtractCPUInfo an error message hinted on missing
character device data which is wrong.

Also a comment states that only qemu-kvm tree includes the thread_id
field. This is no longer true.

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