Returns the status of any current operation to set the next
boot release file. The following values may be returned:
1 (idle) There is no boot release setting
operation in progress.
2 (success) The last boot release setting
operation completed successfully.
3 (failure) The last boot release setting
operation failed.
5 (syncing) A boot release setting operation is
currently in progress and the file is
being syncronised across the stack or
system.
When a read of this object returns a value of 'success' or
'failure', it will immediately be reset to 'idle' and a new
operation may be initiated if desired. A detailed description
of the last completed operation may be determined by reading
nextBootLastSetResult.