Tracking issue - Implement mutex trait in all arch crates

[korken89]

Remove mutex implementation from bare-metal and add new to arch specific crates.

• cortex-m Added arch specific mutex implementation cortex-m#209
• risc-v
• msp430
• more?

[Dirbaio]

Closing this as part of 2024 triage.

the mutex-trait crate is superseded by critical-section, which also allows writing code using mutexes portably across archs. Most arch-support crates already implement it.