Add the missing backslash-newline which was causing make errors.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165098 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Makefile b/Makefile
index 6eec517..2ffe359 100644
--- a/Makefile
+++ b/Makefile
@@ -28,8 +28,8 @@
   OPTIONAL_DIRS :=
 endif
 ifeq ($(BUILD_CLANG_ONLY),YES)
-  DIRS := $(filter-out tools docs unittests, $(DIRS))
-	tools/driver tools/libclang
+  DIRS := $(filter-out tools docs unittests, $(DIRS)) \
+          tools/driver tools/libclang
   OPTIONAL_DIRS :=
 endif