macosx/configure.sh: Enable libsamplerate again

Ulgy resampler produces really noisy output with some samples,
it is way better with libsamplerate.

extras/package/macosx/configure.sh

@@ -34,7 +34,6 @@ OPTIONS="
         --disable-xcb
         --disable-caca
         --disable-sdl
-        --disable-samplerate
         --disable-macosx-dialog-provider
         --with-macosx-version-min=10.6
 "