Update autogen.sh to handle automake 1.10.
Update autogen.sh to handle automake 1.10.

svn path=/trunk/vorbis/; revision=13069

youfearm3/vorbis,youfearm3/vorbis,eidy/vorbis,felipebetancur/vorbis,ksophocleous/vorbis,emscripten-ports/Vorbis,nicolaichuk/vorbis,erikd/vorbis,youfearm3/vorbis,ShiftMediaProject/vorbis,nicolaichuk/vorbis,ksophocleous/vorbis,eidy/vorbis,ShiftMediaProject/vorbis,erikd/vorbis,emscripten-ports/Vorbis,emscripten-ports/Vorbis,ShiftMediaProject/vorbis,mwgoldsmith/vorbis,mwgoldsmith/vorbis,youfearm3/vorbis,nicolaichuk/vorbis,erikd/vorbis,ksophocleous/vorbis,nicolaichuk/vorbis,ShiftMediaProject/vorbis,felipebetancur/vorbis,eidy/vorbis,felipebetancur/vorbis,ksophocleous/vorbis,eidy/vorbis,ShiftMediaProject/vorbis,emscripten-ports/Vorbis,erikd/vorbis,felipebetancur/vorbis,mwgoldsmith/vorbis,ShiftMediaProject/vorbis,mwgoldsmith/vorbis