rusticl/program: print compiler output as Rust string

The CString Debug implementation does not handle new lines, so it gets all
printed as a single row, which is not what we want at all.

Fixes: 01de0ff26f ("rusticl/program: store log as a CString")
Reviewed-by: @LingMan
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/42021>

src/gallium/frontends/rusticl/core/program.rs

@@ -973,7 +973,7 @@ fn debug_logging(p: &Program, devs: &[&Device]) {
         for dev in devs {
             let msg = p.log(dev);
             if !msg.is_empty() {
-                eprintln!("{msg:?}");
+                eprintln!("{}", msg.to_string_lossy());
             }
         }
     }