news: Drop empty sections
news: Drop empty sections

We have occasionally failed to document certain categories
of changes in the release notes, yet still left the
corresponding sections in the file even though they were
completely empty.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>

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