Disable the address-of-ZST test for now; it is buggy as it disagrees with rustc

Author: RalfJung

tests/compile-fail/zst2.rs

@@ -0,0 +1,12 @@
+#![allow(dead_code)]
+
+#[derive(Debug)]
+struct A;
+
+fn main() {
+    // can't use assert_eq, b/c that will try to print the pointer addresses with full MIR enabled
+
+    // FIXME: Test disabled for now, see <https://github.com/solson/miri/issues/131>.
+    //assert!(&A as *const A as *const () == &() as *const _);
+    //assert!(&A as *const A == &A as *const A);
+}