Make -Wunused-value off by default, matching GCC. Fixes rdar://7126194.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@114316 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/enum.c b/test/Sema/enum.c
index 64aa31b..5782cb8 100644
--- a/test/Sema/enum.c
+++ b/test/Sema/enum.c
@@ -44,10 +44,10 @@
     ;
   (_Bool)ve2;  // expected-error {{arithmetic or pointer type is required}}
 
-  for (; ;ve2) // expected-warning {{expression result unused}}
+  for (; ;ve2)
     ;
   (void)ve2;
-  ve2;         // expected-warning {{expression result unused}}
+  ve2;
 }
 
 // PR2416