Remove all possible warnings

[LuernOutOfOrder]

This pull request refactors the serial device and console management code to improve safety, encapsulation, and maintainability. The main changes include replacing global mutable statics with thread-safe structures, introducing new manager types for serial devices and the kernel console, and updating related code to use these abstractions.

Serial device and console management improvements:

• Introduced a SerialManager struct (SERIAL_DEVICES) to encapsulate and safely manage the array of UART devices, replacing the previous global UART_DEVICES static. This adds methods for adding devices and retrieving the default console. [1] [2] [3] [4]
• Added a KernelConsole struct (KCONSOLE) to manage the kernel console in a thread-safe manner, replacing the previous global mutable static. Methods for setting and getting the console were added. [1] [2]
• Updated the print and write_fmt functions in src/print.rs to use the new SerialManager and KernelConsole abstractions, ensuring safer access to shared resources. [1] [2]

Code quality and safety improvements:

• Removed the #![warn(static_mut_refs)] lint, as the new abstractions eliminate the need for direct static mut references.
• Added Copy and Clone derives to DriverRegion and Ns16550 structs for easier and safer usage. [1] [2]

API and naming consistency:

• Renamed the _default_console field in UartDevice to default_console for clarity and consistency. [1] [2]

These changes collectively make serial device and console management more robust and idiomatic in Rust, reducing the risk of data races and undefined behavior.