Add credit for the poll.c emulation layer for BSD

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@12107 65c4cc65-6c06-0410-ace0-fbb531ad65f3

CREDITS

@@ -83,6 +83,8 @@ John Todd - Monkey sounds and associated teletorture prompt
 Michael Jerris - bug marshaling
 Leif Madsen, Jared Smith and Jim van Meggelen - the Asterisk book
 	available under a Creative Commons License at http://www.asteriskdocs.org
+Brian M. Clapper - poll.c emulation
+	This product includes software developed by Brian M. Clapper <bmc@clapper.org>
 
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