arch: Remove unused interrupt functions and unify naming

Refactor interrupt enable/disable function names to use a consistent arch_interrupt_global_enable and arch_interrupt_global_disable naming scheme.

• Update function names in arch_interrupt.h all target architectures.
• Remove redundant definitions of arch_interrupt_global_enable and arch_interrupt_global_disable in architecture-specific source files.
• Adjust inline comments to reflect the new naming convention.
• Add documentation to add a new architecture target