ices/70624.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#70624

macro_rules! breakme {
    ($config:stmt; $($tokens:literal)*) => {
        #[cfg($config)]
        $($tokens)*
    };
}

fn main() {
    macro_rules! unix {
        () => {
            not(unix)
        };
    }

    breakme!(unix!(); "test");
}

=== stdout ===
=== stderr ===
error: expected unsuffixed literal or identifier, found `unix!()`
  --> /home/runner/work/glacier/glacier/ices/70624.rs:3:15
   |
3  |         #[cfg($config)]
   |               ^^^^^^^
...
15 |     breakme!(unix!(); "test");
   |     -------------------------- in this macro invocation
   |
   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

warning: unused macro definition
  --> /home/runner/work/glacier/glacier/ices/70624.rs:9:5
   |
9  | /     macro_rules! unix {
10 | |         () => {
11 | |             not(unix)
12 | |         };
13 | |     }
   | |_____^
   |
   = note: `#[warn(unused_macros)]` on by default

error: aborting due to previous error; 1 warning emitted

==============