Remove generated PDF files on clean

git-svn-id: http://framework.zend.com/svn/framework/standard/trunk@15367 44c647ce-9c0f-0410-b52a-842ac1e357ba

documentation/manual/en/Makefile.in

@@ -133,7 +133,7 @@ clean:
 		rm -Rf html/figures ; \
 	fi
 	-rm -f _temp_*.xml
-	-rm -f ./*.pdf
+	-rm -f /*.pdf
 	-rm -f ZendFramework.fo
 
 cleanall: clean