fixed yet another very potential memleak;

lib/channel.c

@@ -218,7 +218,7 @@ int channel_close(chnl_t *chnl)
 {
   char *uuid_;
   usrtc_node_t *node = NULL;
-  int r;
+  int r = 0;
   conn_t *co = chnl->connection;
   conn_sys_t *ssys = co->ssys;
   sxmsg_t *sms;
@@ -244,9 +244,10 @@ int channel_close(chnl_t *chnl)
 
   uuid_ = __generate_uuid();
   pl = malloc(sizeof(sxpayload_t));
-  if(!pl) {
+  if(!pl || !uuid_) {
     pthread_rwlock_unlock(&(chnl->msglock));
-    free(uuid_);
+    if(pl) free(pl);
+    if(uuid_) free(uuid_);
     return ENOMEM;
   }
   if(__create_sys_msg(&sms, uuid_, chnl, pl)) {