[NFC] Remove extra __has_feature

It's already in Compiler.h

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@367625 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Support/type_traits.h

@@ -17,11 +17,6 @@
 #include <type_traits>
 #include <utility>
 
-#ifndef __has_feature
-#define LLVM_DEFINED_HAS_FEATURE
-#define __has_feature(x) 0
-#endif
-
 namespace llvm {
 
 
@@ -203,8 +198,4 @@ class is_trivially_copyable<T*> : public std::true_type {
 #define LLVM_IS_FINAL(Ty) __is_final(Ty)
 #endif
 
-#ifdef LLVM_DEFINED_HAS_FEATURE
-#undef __has_feature
-#endif
-
 #endif // LLVM_SUPPORT_TYPE_TRAITS_H