common.mk: make unicode header dir

* common.mk (UNICODE_HDR_DIR): make unicode header directory.
  [ruby-core:76879] [Bug #12677]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55944 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

common.mk

@@ -1116,6 +1116,7 @@ $(UNICODE_HDR_DIR)/$(ALWAYS_UPDATE_UNICODE:yes=casefold.h): \
 
 $(UNICODE_HDR_DIR)/casefold.h: $(srcdir)/enc/unicode/case-folding.rb
 	$(Q) $(ALWAYS_UPDATE_UNICODE:yes=exit &&) $(MAKE) $(MFLAGS) Q=$(Q) UNICODE_VERSION=$(UNICODE_VERSION) update-unicode
+	$(MAKEDIRS) $(@D)
 	$(Q) $(BASERUBY) $(srcdir)/enc/unicode/case-folding.rb \
 		--output-file=$@ \
 		--mapping-data-directory=$(UNICODE_SRC_DATA_DIR)