[inductor][scheduler] Use set for origin (#119861)
xref - https://github.com/pytorch/pytorch/issues/119440
This avoids node > node comparison if the origin order is same in the origins tuple. However, I am unable to come up with a test case where this could happen.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/119861
Approved by: https://github.com/Skylion007, https://github.com/eellison
