Cleanup a fixme by using a specific diagnostic for subscripting
a pointer to void.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@133912 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/pointer-addition.c b/test/Sema/pointer-addition.c
index af8258a..21ce63b 100644
--- a/test/Sema/pointer-addition.c
+++ b/test/Sema/pointer-addition.c
@@ -9,7 +9,7 @@
   c += 1;    // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
   c--;       // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
   c -= 1;    // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
-  (void) c[1]; // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
+  (void) c[1]; // expected-warning {{subscript of a pointer to void is a GNU extension}}
   b = 1+b;   // expected-error {{arithmetic on a pointer to an incomplete type}}
   /* The next couple tests are only pedantic warnings in gcc */
   void (*d)(S*,void*) = a;