Fix missed extension replacement

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@43347 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/h323/Makefile.in

@@ -35,7 +35,7 @@ $(SOURCES)::	Makefile ../../Makefile
 libchanh323.a:	$(OBJS)
 	ar crv $@ $(OBJS)
 
-cisco-h225.cpp::	cisco-h225.asn
+cisco-h225.cxx::	cisco-h225.asn
 	asnparser -m CISCO_H225 -c $<
 
 Makefile.ast: