cmake: revert r149496

It *looks* like this caused PR11903, somehow.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149540 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index bb92fee..3a1c12e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -223,7 +223,6 @@
   FILES_MATCHING
   PATTERN "*.def"
   PATTERN "*.h"
-  PATTERN "config.h" EXCLUDE
   PATTERN ".svn" EXCLUDE
   )