Remove doc/linkedlists.txt as it is no longer needed. The top of the file reads:

As of 2004-12-23, this documentation is no longer maintained. The doxygen documentation
generated from linkedlists.h should be referred to in its place, as it is more complete
and better maintained.


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@44877 65c4cc65-6c06-0410-ace0-fbb531ad65f3