docs: Improve PCI topology and hotplug guidelines
docs: Improve PCI topology and hotplug guidelines

Address some minor flaws in the original document that
were pointed out during review.

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

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