Tighten format string diagnostic and make it a bit clearer (and a bit closer to GCC's).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148579 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Analysis/taint-generic.c b/test/Analysis/taint-generic.c
index 65e519e..be20f2c 100644
--- a/test/Analysis/taint-generic.c
+++ b/test/Analysis/taint-generic.c
@@ -65,7 +65,7 @@
 
 void scanfArg() {
   int t = 0;
-  scanf("%d", t); // expected-warning {{conversion specifies type 'int *' but the argument has type 'int'}}
+  scanf("%d", t); // expected-warning {{format specifies type 'int *' but the argument has type 'int'}}
 }
 
 void bufferGetchar(int x) {