fix automake warning
fix automake warning

Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard,Hiroyuki-Nagata/XrossBoard