Rollup merge of #115427 - solid-rs:patch/kmc-solid/is-interrupted, r=cuviper

kmc-solid: Fix `is_interrupted`

Follow-up to #115228. Fixes a build error in [`*-kmc-solid_*`](https://doc.rust-lang.org/nightly/rustc/platform-support/kmc-solid.html) Tier 3 targets.

```
error[E0603]: function `is_interrupted` is private
  --> library\std\src\sys\solid\mod.rs:77:12
   |
77 |     error::is_interrupted(code)
   |            ^^^^^^^^^^^^^^ private function
   |
note: the function `is_interrupted` is defined here
  --> library\std\src\sys\solid\error.rs:35:1
   |
35 | fn is_interrupted(er: abi::ER) -> bool {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```

Author: matthiaskrgr