Rollup merge of #95916 - solid-rs:feat-kmc-solid-abort, r=Mark-Simulacrum

Rollup merge of #95916 - solid-rs:feat-kmc-solid-abort, r=Mark-Simulacrum

kmc-solid: Use `libc::abort` to abort a program

This PR updates the target-specific abort subroutine for the [`*-kmc-solid_*`](https://doc.rust-lang.org/nightly/rustc/platform-support/kmc-solid.html) Tier 3 targets.

The current implementation uses a `hlt` instruction, which is the most direct way to notify a connected debugger but is not the most flexible way. This PR changes it to call the `abort` libc function, making it possible for a system designer to override its behavior as they see fit.