gmake.mk: update timestamp of des_tables.c
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55276 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
gmake.mk: update timestamp of des_tables.c
timestamp unless make_des_table failed.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55276 b2dd03c8-39d4-4d8f-98ff-823fe69b080e