Prevent extra new line when not using buffer in zlog stream

Author: bukka

sapi/fpm/fpm/zlog.c

@@ -510,10 +510,12 @@ zlog_bool zlog_stream_finish(struct zlog_stream *stream) /* {{{ */
 #endif
 		stream->buf[stream->len++] = '\n';
 		zlog_stream_write(stream, stream->buf, stream->len);
-	} else {
+	} else if (!stream->finished) {
 		zlog_stream_write(stream, "\n", 1);
 	}
 
+	stream->finished = 1;
+
 	return 1;
 }
 /* }}} */