build the new runtime directory


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7876 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Makefile b/Makefile
index b7824d5..735ba5f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 LEVEL = .
-DIRS = lib/Support utils lib tools
+DIRS = lib/Support utils lib tools runtime
 OPTIONAL_DIRS = projects
 
 include $(LEVEL)/Makefile.common