Further Coverity Scan fixes.

src/conf.c

@@ -722,6 +722,7 @@ int config__read_file_core(struct mosquitto__config *config, bool reload, const
 						return MOSQ_ERR_NOMEM;
 					}else if(STREMPTY(key)){
 						log__printf(NULL, MOSQ_LOG_ERR, "Error: Invalid auth_opt_ config option.");
+						mosquitto__free(key);
 						return MOSQ_ERR_INVAL;
 					}
 					token += 9+strlen(key)+1;
@@ -733,6 +734,7 @@ int config__read_file_core(struct mosquitto__config *config, bool reload, const
 						cur_auth_plugin_config->options = mosquitto__realloc(cur_auth_plugin_config->options, cur_auth_plugin_config->option_count*sizeof(struct mosquitto_auth_opt));
 						if(!cur_auth_plugin_config->options){
 							log__printf(NULL, MOSQ_LOG_ERR, "Error: Out of memory.");
+							mosquitto__free(key);
 							return MOSQ_ERR_NOMEM;
 						}
 						cur_auth_plugin_config->options[cur_auth_plugin_config->option_count-1].key = key;

src/net.c

@@ -124,7 +124,9 @@ int net__socket_accept(struct mosquitto_db *db, mosq_sock_t listensock)
 
 	if(db->config->set_tcp_nodelay){
 		int flag = 1;
-		setsockopt(new_sock, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(int));
+		if(setsockopt(new_sock, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(int) != 0)){
+			log__printf(NULL, MOSQ_LOG_WARNING, "Warning: Unable to set TCP_NODELAY.");
+		}
 	}
 
 	new_context = context__init(db, new_sock);