[asan] rely on __has_feature(address_sanitizer) instead of the ADDRESS_SANITIZER macro

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@147297 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/asan/asan_interface.h b/lib/asan/asan_interface.h
index 72ec126..7506586 100644
--- a/lib/asan/asan_interface.h
+++ b/lib/asan/asan_interface.h
@@ -75,7 +75,7 @@
   void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
 
 // User code should use macro instead of functions.
-#ifdef ADDRESS_SANITIZER
+#if defined(__has_feature) && __has_feature(address_sanitizer)
 #define ASAN_POISON_MEMORY_REGION(addr, size) \
   __asan_poison_memory_region((addr), (size))
 #define ASAN_UNPOISON_MEMORY_REGION(addr, size) \