event_virtual: Fix several missing lock_release() ops

Credits to @ryancaicse for the report in #2714

(cherry picked from commit e958b02)

modules/event_virtual/event_virtual.c

@@ -466,6 +466,7 @@ static int failover_raise(struct sip_msg *msg, str *ev_name,
 
 				cb_param->evi_params = evi_dup_shm_params(params);
 				if (!cb_param->evi_params) {
+					lock_release(cur_sock->lock);
 					LM_ERR("Failed to dup evi params in shm\n");
 					shm_free(cb_param);
 					return -1;
@@ -616,13 +617,15 @@ static int virtual_raise(struct sip_msg *msg, str* ev_name, evi_reply_sock *sock
 				LM_ERR("unable to parse socket %.*s\n",
 						vsock->current_sock->sock_str.len,
 						vsock->current_sock->sock_str.s);
+				lock_release(rrobin_lock);
 				return -1;
 			}
 
 			if (vsock->current_sock->trans_mod->raise(msg, ev_name,
 				vsock->current_sock->sock, params, &async_status)) {
 				LM_ERR("unable to raise socket %.*s\n",
 						vsock->current_sock->sock_str.len, vsock->current_sock->sock_str.s);
+				lock_release(rrobin_lock);
 				return -1;
 			}
 
@@ -650,8 +653,10 @@ static void virtual_free(evi_reply_sock *sock) {
 	lock_get(global_lock);
 
 	vsock = (struct virtual_socket *)sock->params;
-	if (!vsock)
+	if (!vsock) {
+		lock_release(global_lock);
 		return;
+	}
 
 	/* free the list of sockets for this virtual socket */
 	sub_list = vsock->list_sockets;