Do clean for h323 directory too

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@43334 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/Makefile

@@ -66,6 +66,8 @@ clean::
 ifneq ($(wildcard h323/Makefile.ast),)
   include h323/Makefile.ast
 H323LDFLAGS += -Wl,--version-script=h323/noexport.map
+clean::
+	$(MAKE) -C h323 clean
 else
 h323/libchanh323.a h323/Makefile.ast:
 	$(CMD_PREFIX) $(MAKE) -C h323