Switch autogen.sh to use autoreconf
Switch autogen.sh to use autoreconf

The previous version didn't actually update everything needed
(like config.{guess,sub} at the very least).

ksophocleous/speex,lowlevel-studios/speex-android,mwgoldsmith/speex,felipebetancur/speex,felipebetancur/speex,lu-zero/speex,ksophocleous/speex,lowlevel-studios/speex-android,lu-zero/speex,ksophocleous/speex,felipebetancur/speex,lu-zero/speex,mwgoldsmith/speex,felipebetancur/speex,mwgoldsmith/speex,lowlevel-studios/speex-android,mwgoldsmith/speex