Add support for pow (#52374)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/18627
Adds pow support for JIT
Pull Request resolved: https://github.com/pytorch/pytorch/pull/52374
Test Plan: python test/test_jit.py -k test_torch_pow
Reviewed By: heitorschueroff
Differential Revision: D26555070
Pulled By: nikithamalgifb
fbshipit-source-id: 0d325f09cf893e4ae50277a95a6b7ad67d94f342
