northd: Make the enclose handling less error prone

The enclose handling was working for all cases
except the drop. Make sure that the enclose is
properly defined for that case and make sure
that it is used properly.

Fixes: cf205ca ("northd: Fix missig "); " from LB flows")
Signed-off-by: Ales Musil <amusil@redhat.com>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
(cherry picked from commit ce7f482)

northd/northd.c

@@ -9951,6 +9951,7 @@ build_lrouter_nat_flows_for_lb(struct ovn_lb_vip *lb_vip,
                                        lb->selection_fields, false,
                                        features->ct_no_masked_label);
     bool drop = !!strncmp(ds_cstr(action), "ct_lb", strlen("ct_lb"));
+    const char *enclose = drop ? "" : ");";
     if (!drop) {
         /* Remove the trailing ");". */
         ds_truncate(action, action->length - 2);
@@ -9976,8 +9977,8 @@ build_lrouter_nat_flows_for_lb(struct ovn_lb_vip *lb_vip,
         const char *skip_snat = features->ct_lb_related && !drop
                                 ? "; skip_snat"
                                 : "";
-        skip_snat_new_action = xasprintf("flags.skip_snat_for_lb = 1; %s%s);",
-                                         ds_cstr(action), skip_snat);
+        skip_snat_new_action = xasprintf("flags.skip_snat_for_lb = 1; %s%s%s",
+                                         ds_cstr(action), skip_snat, enclose);
         skip_snat_est_action = xasprintf("flags.skip_snat_for_lb = 1; "
                                          "next;");
     }
@@ -10040,11 +10041,9 @@ build_lrouter_nat_flows_for_lb(struct ovn_lb_vip *lb_vip,
     const char *force_snat = features->ct_lb_related && !drop
                              ? "; force_snat"
                              : "";
-    force_snat_new_action = xasprintf("flags.force_snat_for_lb = 1; %s%s);",
-                                      ds_cstr(action), force_snat);
-    if (!drop) {
-        ds_put_cstr(action, ");");
-    }
+    force_snat_new_action = xasprintf("flags.force_snat_for_lb = 1; %s%s%s",
+                                      ds_cstr(action), force_snat, enclose);
+    ds_put_cstr(action, enclose);
 
     for (size_t i = 0; i < lb->n_nb_lr; i++) {
         struct ovn_datapath *od = lb->nb_lr[i];