lxc: use job functions in lxcDomainSetMemoryFlags
lxc: use job functions in lxcDomainSetMemoryFlags

Large balloon operation can be time consuming.  Use the recently
added job functions and unlock the virDomainObj while ballooning.

Signed-off-by: Katerina Koukiou <2601125deb717345fbc1a69eaf8ffe9a28fa5fe9@gmail.com>

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