Replace all unwrap with better error handling

[LuernOutOfOrder]

This pull request focuses on improving error handling and code robustness across several device initialization and FDT (Flattened Device Tree) helper functions. The main changes involve replacing unwrap() calls with explicit error messages using expect(), which provides clearer diagnostics in case of failure. Additionally, some minor code style improvements and lint suppressions have been introduced for better code quality.

Error handling improvements

• Replaced all unwrap() calls with expect() and descriptive error messages in device initialization routines and FDT property accessors, improving diagnostics and preventing silent panics. (src/devices/mod.rs, src/devices/serials/ns16550.rs, src/dtb/helpers.rs, src/dtb/mod.rs) [1] [2] [3] [4] [5] [6] [7]

Code style and linting

• Added #[allow(clippy::needless_range_loop)] annotations to suppress Clippy lint warnings in loops where the range loop is intentional. (src/devices/serials/ns16550.rs, src/dtb/helpers.rs) [1] [2]

Minor robustness improvements

• Changed error handling in print() to ignore formatting errors instead of panicking, making printing more robust. (src/print.rs)

These changes collectively make the codebase safer and easier to debug by surfacing meaningful error messages and preventing unexpected panics.