lib: parser: remove incorrect assert

A {foo|bar|baz} graph node will have more than 1/2 incoming links even
if no other references are left to it (which is what the assert was
previously trying to ensure.)

I don't see a good way to "fix" the assert so I'm just removing it.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

lib/command_graph.c

@@ -348,8 +348,6 @@ cmd_merge_nodes (struct graph *oldgraph, struct graph *newgraph,
       /* nothing found => add new to old */
       if (i == vector_active (old->to) && direction > 0)
         {
-          assert (vector_count (cnew->from) ==
-                          (cmd_nodes_link (cnew, cnew) ? 2 : 1));
           graph_remove_edge (new, cnew);
 
           cmd_reparent_tree (newgraph, oldgraph, cnew);