Add support for backend to register reducer timer
Currently by default, reduce timer registration
is expected for all backend. if timer is not
registered throws assert in set_runtime_stats_and_log()
To allow registration of reducer timer for other
backends, moved the timer registration to another
file decoupling the internal interface.
Signed-off-by: Jeeja <jeejakp@habana.ai>
Fixes #ISSUE_NUMBER
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71700
Approved by: https://github.com/rohan-varma
