Fix or silence clippy warnings on nightly

Fix:
- dead_code
- clippy::if_then_panic
- clippy::manual_memcpy
- clippy::needless_borrow

Silence:
- clippy::missing_safety_doc
- clippy::needless_range_loop
- clippy::single_match

Signed-off-by: Tim Crawford <tcrawford@system76.com>

tool/src/lib.rs

@@ -14,6 +14,9 @@
 //!    compiler. It is only recommended to use these in firmware, as mutual exclusion is not
 //!    guaranteed.
 
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::needless_range_loop)]
+
 #![cfg_attr(not(feature = "std"), no_std)]
 
 #[cfg(not(feature = "std"))]