Resolves two related issues:
- OS_TaskGetId does not return a valid value for tasks where cancellation
  is pending, but they are still running.  This in turn is likely to trigger
  other (bogus) debug checks which invoke OS_DEBUG and in turn do console writes.
- The console write itself is a cancellation point, which is now done while
  holding a BSP mutex.  If canceled here, then the mutex is not released.

Solution is in two parts:
- OS_TaskGetId should return the task ID it knows about, regardless of whether
  the task is pending cancellation or not.
- Defer cancellation of the task while the BSP is locked, ensure it reaches the
  unlock, then restore the previous cancel state.

Fix #1027, defer cancellation when BSP locked

Fix #991, Add count sem timeout test