message: Fix building on Android
diff: @@ -274,7 +274,7 @@ impl<'tu, 'ge> TypeRefExt for TypeRef<'tu, 'ge> {
  return format!("u8::try_from({name})?", name = name);
  }
  Some(Signedness::Signed) => {
  - return format!("u8::try_from({name})? as c_char", name = name);
  + return format!("u8::try_from({name})? as i8", name = name);
  }
  None => {}
  }
  