rename file per crichter's request

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@40310 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_misdn_config.c b/channels/misdn_config.c
similarity index 100%
rename from channels/chan_misdn_config.c
rename to channels/misdn_config.c