qemu: Forbid pinning vCPUs for TCG domain
qemu: Forbid pinning vCPUs for TCG domain

We don't support cpu pinning for TCG domains because QEMU runs them in
one thread only.  But vcpupin command was able to set them, which
resulted in a failed startup, so make sure that doesn't happen.

Signed-off-by: Chen Hanxiao <818f8a165c25fa146ecad28e2ef3e3fb996fa364@gmail.com>

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