ovn-controller: Restore ct zone assignment.

ovn-controller: Restore ct zone assignment.

Recent commits reorganizing bindings handling and also moving ct zone
assignment to ovn-controller.c caused ct zone assignment to no longer
work.  The code relies on an "all_lports" sset that should contain all
logical ports that we should be assigning ct zones for.  Prior to this
change, all_lports was always empty.

Signed-off-by: Babu Shanmugam <bschanmu@redhat.com>
Co-authored-by: Russell Bryant <russell@ovn.org>
Signed-off-by: Russell Bryant <russell@ovn.org>
Acked-by: Ryan Moats <rmoats@us.ibm.com>