FS-7553 reduce soundtouch library requirement to version 1.7.1- this was the…

FS-7553 reduce soundtouch library requirement to version 1.7.1- this was the version bundled with freeswitch

configure.ac

@@ -1334,7 +1334,7 @@ PKG_CHECK_MODULES([OPUS], [opus >= 1.1],[
   AM_CONDITIONAL([HAVE_OPUS],[true])],[
   AC_MSG_RESULT([no]); AM_CONDITIONAL([HAVE_OPUS],[false])])
 
-PKG_CHECK_MODULES([SOUNDTOUCH], [soundtouch >= 1.8.0],[
+PKG_CHECK_MODULES([SOUNDTOUCH], [soundtouch >= 1.7.1],[
   AM_CONDITIONAL([HAVE_SOUNDTOUCH],[true])],[
   AC_MSG_RESULT([no]); AM_CONDITIONAL([HAVE_SOUNDTOUCH],[false])])