Fixing this test which failed due to different warnings

GitOrigin-RevId: ead449aee4c1bd3ad309185528c430fdbd06cf2f
diff --git a/test/Sema/builtins-elementwise-math.c b/test/Sema/builtins-elementwise-math.c
index 19e9c00..4008f77 100644
--- a/test/Sema/builtins-elementwise-math.c
+++ b/test/Sema/builtins-elementwise-math.c
@@ -60,7 +60,7 @@
   enum f { three };
   enum f x = __builtin_elementwise_max(one, three);
 
-  _BitInt(32) ext;
+  _BitInt(32) ext; // expected-warning {{'_BitInt' in C17 and earlier is a Clang extension}}
   ext = __builtin_elementwise_max(ext, ext);
 
   const int ci;
@@ -112,7 +112,7 @@
   enum f { three };
   enum f x = __builtin_elementwise_min(one, three);
 
-  _BitInt(32) ext;
+  _BitInt(32) ext; // expected-warning {{'_BitInt' in C17 and earlier is a Clang extension}}
   ext = __builtin_elementwise_min(ext, ext);
 
   const int ci;