change the dynamo benchmark timeout as a parameter (#94284)
Change the dynamo benchmark timeout from hard code to a parameter with default value 1200ms, cause the hard code 1200ms timeout led some single thread mode model crashed on CPU platform. With the parameter, users can specify the timeout freely.
Fixes #94281
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94284
Approved by: https://github.com/malfet
