Don't call a function in function-arguments-naked.rs

Fixes rust-lang#75096

It's U.B. to use anything other than inline assmebling in a naked
function. Fortunately, the `#break` directive works fine without
anything in the function body.

src/test/debuginfo/function-arguments-naked.rs

@@ -34,7 +34,5 @@ fn main() {
 
 #[naked]
 fn naked(x: usize, y: usize) {
-    zzz(); // #break
+    // #break
 }
-
-fn zzz() { () }