replace sed with tr to remove \r from downloaded file

On some systems, sed does not recognize \r in the pattern the way it
was used here.
Use tr instead because this works the same across systems.

(closes issue #14936)
Reported by: leobrown
Patches: 
      2009042201_14936.diff.txt uploaded by mvanbaak (license 7)
	  Tested by: leobrown, mvanbaak


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@189849 65c4cc65-6c06-0410-ace0-fbb531ad65f3

contrib/scripts/get_ilbc_source.sh

@@ -22,7 +22,7 @@ read tmp
 
 wget -P codecs/ilbc http://www.ietf.org/rfc/rfc3951.txt
 
-wget -q -O - http://www.ilbcfreeware.org/documentation/extract-cfile.awk | sed -e 's/\r//g' > codecs/ilbc/extract-cfile.awk
+wget -q -O - http://www.ilbcfreeware.org/documentation/extract-cfile.awk | tr -d '\r' > codecs/ilbc/extract-cfile.awk
 
 (cd codecs/ilbc && awk -f extract-cfile.awk rfc3951.txt)