Update compile fail tests to use isize.

src/test/compile-fail/refutable-pattern-in-fn-arg.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 fn main() {
-    let f = |&: 3: int| println!("hello");
+    let f = |&: 3: isize| println!("hello");
     //~^ ERROR refutable pattern in function argument: `_` not covered
     f(4);
 }