update makefile.am to support out-of-tree builds

Conflicts:

	Makefile.am
diff --git a/Makefile.am b/Makefile.am
index 5a999eb..f5c6be7 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -30,22 +30,22 @@
 	cd $(top_builddir)/doc && tar cf html.tar */html
 
 $(top_builddir)/doc/core/html/index.html: $(SOURCES) Doxyfile
-	rm -rf doc/core
+	@rm -rf doc/core
 	mkdir -p doc/core
 	$(DOXYGEN) Doxyfile
 
 $(top_builddir)/doc/gsm/html/index.html: $(SOURCES) Doxyfile.gsm
-	rm -rf doc/gsm
+	@rm -rf doc/gsm
 	mkdir -p doc/gsm
 	$(DOXYGEN) Doxyfile.gsm
 
 $(top_builddir)/doc/vty/html/index.html: $(SOURCES) Doxyfile.vty
-	rm -rf doc/vty
+	@rm -rf doc/vty
 	mkdir -p doc/vty
 	$(DOXYGEN) Doxyfile.vty
 
 $(top_builddir)/doc/codec/html/index.html: $(SOURCES) Doxyfile.codec
-	rm -rf doc/codec
+	@rm -rf doc/codec
 	mkdir -p doc/codec
 	$(DOXYGEN) Doxyfile.codec
 
@@ -53,6 +53,6 @@
 	cd $(DESTDIR)$(doc_htmldir) && tar xf html.tar && rm -f html.tar
 
 uninstall-hook:
-	cd $(DESTDIR)$(doc_htmldir) && rm -f *
+	cd $(DESTDIR)$(doc_htmldir) && rm -rf *
 
 endif