Rollup merge of rust-lang#81481 - lcnr:cast-tests, r=jackh726

move some tests

Author: jonas-schievink

src/test/ui/fat-ptr-cast-rpass.rs renamed to src/test/ui/cast/fat-ptr-cast-rpass.rs

@@ -0,0 +1,5 @@
+struct A;
+
+fn main() {
+  println!("{:?}", 1.0 as *const A); //~ERROR  casting `f64` as `*const A` is invalid
+}

src/test/ui/fat-ptr-cast.rs renamed to src/test/ui/cast/fat-ptr-cast.rs

@@ -1,7 +1,7 @@
 error[E0606]: casting `f64` as `*const A` is invalid
-  --> $DIR/unsupported-cast.rs:6:20
+  --> $DIR/unsupported-cast.rs:4:20
    |
-LL |   println!("{:?}", 1.0 as *const A); // Can't cast float to foreign.
+LL |   println!("{:?}", 1.0 as *const A);
    |                    ^^^^^^^^^^^^^^^
 
 error: aborting due to previous error