Fix apparmor issues for tck

The network and nwfilter tests contained in the libvirt-TCK testkit can fail
unless access to raw network packets is granted. Without this access, the
following apparmor error can be seen while running the tests:

  apparmor="DENIED" operation="create" parent=1 profile="/usr/sbin/libvirtd"
  pid=94731 comm="libvirtd" family="packet" sock_type="raw" protocol=768

examples/apparmor/usr.sbin.libvirtd

@@ -35,6 +35,7 @@
   network inet6 stream,
   network inet6 dgram,
   network packet dgram,
+  network packet raw,
 
   # Very lenient profile for libvirtd since we want to first focus on confining
   # the guests. Guests will have a very restricted profile.