Add dependency on bundled yaml.h when using

ext/psych/depend

@@ -1,3 +1,5 @@
+$(OBJS): $(YAML_H)
+
 # AUTOGENERATED DEPENDENCIES START
 psych.o: $(RUBY_EXTCONF_H)
 psych.o: $(arch_hdrdir)/ruby/config.h

ext/psych/extconf.rb

@@ -32,8 +32,11 @@ if enable_config("bundled-libyaml", false) || !(find_header('yaml.h') && find_li
 
   find_header 'yaml.h'
   have_header 'config.h'
+  bundled = true
 end
 
-create_makefile 'psych'
+create_makefile 'psych' do |mk|
+  mk << "YAML_H =#{' yaml/yaml.h' if bundled}\n"
+end
 
 # :startdoc: