Developing and refactoring vm and buf system

- Renaming vralloc functions to implement bsd like buffer interface
- Started to implement io buffers
- Added atomic integer
- Refactoring mtx_t
- Implementing ticket lock for mtx_t
- Refactoring dev interface

Known defects:
Atomic integer functions seem to fail and stall on real hw
=> ticket locking is not functioning on real hw

Main issue again that ldrex/strex is not working properly for some
reason.