network: make routing_policy_rule_free() returns NULL

src/network/networkd-routing-policy-rule.c

@@ -84,10 +84,9 @@ static int routing_policy_rule_new_static(Network *network, const char *filename
         return 0;
 }
 
-void routing_policy_rule_free(RoutingPolicyRule *rule) {
-
+RoutingPolicyRule *routing_policy_rule_free(RoutingPolicyRule *rule) {
         if (!rule)
-                return;
+                return NULL;
 
         if (rule->network) {
                 LIST_REMOVE(rules, rule->network->rules, rule);
@@ -108,7 +107,8 @@ void routing_policy_rule_free(RoutingPolicyRule *rule) {
         network_config_section_free(rule->section);
         free(rule->iif);
         free(rule->oif);
-        free(rule);
+
+        return mfree(rule);
 }
 
 static int routing_policy_rule_copy(RoutingPolicyRule *dest, RoutingPolicyRule *src) {

src/network/networkd-routing-policy-rule.h

@@ -57,7 +57,7 @@ struct RoutingPolicyRule {
 };
 
 int routing_policy_rule_new(RoutingPolicyRule **ret);
-void routing_policy_rule_free(RoutingPolicyRule *rule);
+RoutingPolicyRule *routing_policy_rule_free(RoutingPolicyRule *rule);
 
 DEFINE_NETWORK_SECTION_FUNCTIONS(RoutingPolicyRule, routing_policy_rule_free);
 int routing_policy_rule_section_verify(RoutingPolicyRule *rule);