refcnt: refcnt is unsigned, fix comparisons

This does not make a difference, but the code was confusing.

src/libsystemd-network/sd-dhcp-client.c

@@ -1672,7 +1672,7 @@ sd_dhcp_client *sd_dhcp_client_ref(sd_dhcp_client *client) {
 }
 
 sd_dhcp_client *sd_dhcp_client_unref(sd_dhcp_client *client) {
-        if (client && REFCNT_DEC(client->n_ref) <= 0) {
+        if (client && REFCNT_DEC(client->n_ref) == 0) {
                 log_dhcp_client(client, "FREE");
 
                 client_initialize(client);

src/libsystemd-network/sd-dhcp-lease.c

@@ -193,7 +193,7 @@ sd_dhcp_lease *sd_dhcp_lease_ref(sd_dhcp_lease *lease) {
 }
 
 sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) {
-        if (lease && REFCNT_DEC(lease->n_ref) <= 0) {
+        if (lease && REFCNT_DEC(lease->n_ref) == 0) {
                 free(lease->hostname);
                 free(lease->domainname);
                 free(lease->dns);

src/libsystemd-network/sd-dhcp6-client.c

@@ -1254,7 +1254,7 @@ sd_dhcp6_client *sd_dhcp6_client_ref(sd_dhcp6_client *client) {
 }
 
 sd_dhcp6_client *sd_dhcp6_client_unref(sd_dhcp6_client *client) {
-        if (client && REFCNT_DEC(client->n_ref) <= 0) {
+        if (client && REFCNT_DEC(client->n_ref) == 0) {
                 client_reset(client);
 
                 sd_dhcp6_client_detach_event(client);

src/libsystemd-network/sd-dhcp6-lease.c

@@ -195,7 +195,7 @@ sd_dhcp6_lease *sd_dhcp6_lease_ref(sd_dhcp6_lease *lease) {
 }
 
 sd_dhcp6_lease *sd_dhcp6_lease_unref(sd_dhcp6_lease *lease) {
-        if (lease && REFCNT_DEC(lease->n_ref) <= 0) {
+        if (lease && REFCNT_DEC(lease->n_ref) == 0) {
                 free(lease->serverid);
                 dhcp6_lease_free_ia(&lease->ia);
 

src/libsystemd-network/sd-icmp6-nd.c

@@ -145,7 +145,7 @@ static int icmp6_nd_init(sd_icmp6_nd *nd) {
 }
 
 sd_icmp6_nd *sd_icmp6_nd_unref(sd_icmp6_nd *nd) {
-        if (nd && REFCNT_DEC(nd->n_ref) <= 0) {
+        if (nd && REFCNT_DEC(nd->n_ref) == 0) {
 
                 icmp6_nd_init(nd);
                 sd_icmp6_nd_detach_event(nd);

src/libsystemd-network/sd-ipv4ll.c

@@ -605,7 +605,7 @@ sd_ipv4ll *sd_ipv4ll_ref(sd_ipv4ll *ll) {
 }
 
 sd_ipv4ll *sd_ipv4ll_unref(sd_ipv4ll *ll) {
-        if (ll && REFCNT_DEC(ll->n_ref) <= 0) {
+        if (ll && REFCNT_DEC(ll->n_ref) == 0) {
                 ll->receive_message =
                         sd_event_source_unref(ll->receive_message);
                 ll->fd = safe_close(ll->fd);