Add target_triple to Clang site configuration.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@85881 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/lit.site.cfg.in b/test/lit.site.cfg.in
index 9dabafc..c88c90b 100644
--- a/test/lit.site.cfg.in
+++ b/test/lit.site.cfg.in
@@ -5,6 +5,7 @@
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.llvm_libs_dir = "@LLVM_LIBS_DIR@"
 config.clang_obj_root = "@CLANG_BINARY_DIR@"
+config.target_triple = "@TARGET_TRIPLE@"
 
 # Let the main config do the real work.
 lit.load_config(config, "@CLANG_SOURCE_DIR@/test/lit.cfg")