asterisk-1.4.23.1 : Checksum changed on source package.

asterisk-1.4.23.1 : Checksum changed on source package.
                    * Updated checksum to new values.
                    * Dropped sounds.xml.patch so recipe builds.

The Asterisk people changed the source tarballs for legal reasons. This
blog entry explains the music-on-hold changes:

http://blogs.digium.com/2009/08/18/asterisk-music-on-hold-changes/

I made the minimum updates so the recipe builds again. We'll need
someone familiar with Asterisk to work out what else needs changing.