Do not suggest "is a function" for free variables

Part of #82323

src/test/ui/functions-closures/fn-help-with-err-generic-is-not-function.rs

@@ -0,0 +1,22 @@
+struct Struct<T>(T);
+impl Struct<T>
+//~^ ERROR cannot find type `T` in this scope
+//~| NOTE not found in this scope
+//~| HELP you might be missing a type parameter
+where
+    T: Copy,
+    //~^ ERROR cannot find type `T` in this scope
+    //~| NOTE not found in this scope
+{
+    // The part where it claims that there is no method named `len` is a bug. Feel free to fix it.
+    // This test is intended to ensure that a different bug, where it claimed
+    // that `v` was a function, does not regress.
+    fn method(v: Vec<u8>) { v.len(); }
+    //~^ ERROR type annotations needed
+    //~| NOTE cannot infer type
+    //~| NOTE type must be known at this point
+    //~| ERROR no method named `len`
+    //~| NOTE private field, not a method
+}
+
+fn main() {}