- Initialize "--no-builtin" to "false".

- Testcase for r56885.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56886 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/SelectionDAG/SelectionDAG.cpp

@@ -42,7 +42,7 @@
 using namespace llvm;
 
 static cl::opt<bool>
-NoBuiltin("no-builtin",
+NoBuiltin("no-builtin", cl::init(false),
            cl::desc("Don't recognize built-in functions that do not begin "
                     "with `__builtin_' as prefix"));