Add test batch 2

tests/ui/function-pointer/function-pointer-comparison-54696.rs

@@ -0,0 +1,11 @@
+// https://github.com/rust-lang/rust/issues/54696
+//@ run-pass
+
+#![allow(unpredictable_function_pointer_comparisons)]
+
+fn main() {
+    // We shouldn't promote this
+    let _ = &(main as fn() == main as fn());
+    // Also check nested case
+    let _ = &(&(main as fn()) == &(main as fn()));
+}