remove type system tests

tests/compile-fail/cast_fn_ptr_unsafe.rs

@@ -1,10 +0,0 @@
-// just making sure that fn -> unsafe fn casts are handled by rustc so miri doesn't have to
-fn main() {
-    fn f() {}
-
-    let g = f as fn() as unsafe fn(i32); //~ERROR: non-primitive cast: `fn()` as `unsafe fn(i32)`
-
-    unsafe {
-        g(42);
-    }
-}

tests/compile-fail/cast_fn_ptr_unsafe2.rs

@@ -1,10 +0,0 @@
-// just making sure that fn -> unsafe fn casts are handled by rustc so miri doesn't have to
-fn main() {
-    fn f() {}
-
-    let g = f as fn() as fn(i32) as unsafe fn(i32); //~ERROR: non-primitive cast: `fn()` as `fn(i32)`
-
-    unsafe {
-        g(42);
-    }
-}