support "make distclean" as well as "make dist-clean" for the picky people

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@23208 65c4cc65-6c06-0410-ace0-fbb531ad65f3

Makefile

@@ -564,6 +564,8 @@ clean: clean-depend
 	$(MAKE) -C db1-ast clean
 	$(MAKE) -C stdtime clean
 
+distclean: dist-clean
+
 dist-clean: clean
 	rm -f menuselect.makeopts makeopts makeopts.xml
 	rm -f config.log config.status