Make clang-tblgen's Makefile independent of Clang's top-level Makefile,
to avoid having to make it available for the cross build when it
builds only clang-tblgen.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141453 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/Makefile b/utils/TableGen/Makefile
index b92da83..9790efc 100644
--- a/utils/TableGen/Makefile
+++ b/utils/TableGen/Makefile
@@ -7,7 +7,7 @@
 #
 ##===----------------------------------------------------------------------===##
 
-CLANG_LEVEL = ../..
+LEVEL = ../../../..
 TOOLNAME = clang-tblgen
 USEDLIBS = LLVMTableGen.a LLVMSupport.a
 REQUIRES_EH := 1
@@ -16,4 +16,4 @@
 # This tool has no plugins, optimize startup time.
 TOOL_NO_EXPORTS = 1
 
-include $(CLANG_LEVEL)/Makefile
+include $(LEVEL)/Makefile.common