review comment: reword test comment

src/test/ui/issues/issue-15919-32.rs

@@ -8,5 +8,5 @@ fn main() {
     let x = [0usize; 0xffff_ffff]; //~ ERROR too big
 }
 
-// These two tests need to have different literals, as we can't rely on conditional compilation
-// for them while retaining the same spans/lines.
+// This and the -64 version of this test need to have different literals, as we can't rely on
+// conditional compilation for them while retaining the same spans/lines.

src/test/ui/issues/issue-15919-64.rs

@@ -8,5 +8,5 @@ fn main() {
     let x = [0usize; 0xffff_ffff_ffff_ffff]; //~ ERROR too big
 }
 
-// These two tests need to have different literals, as we can't rely on conditional compilation
-// for them while retaining the same spans/lines.
+// This and the -32 version of this test need to have different literals, as we can't rely on
+// conditional compilation for them while retaining the same spans/lines.