Add forward AD for torch.linalg.eigh (#62163)
Summary:
This PR adds forward mode differentiation for `torch.linalg.eigh` and a few other functions required for tests to pass.
For some reason running tests for `torch.linalg.eigvalsh` and complex `torch.linalg.eigh` hangs. These tests are skipped for now.
cc ezyang albanD zou3519 gqchen pearu nikitaved soulitzer Lezcano Varal7 jianyuh mruberry heitorschueroff walterddr IvanYashchuk xwang233
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62163
Reviewed By: jbschlosser
Differential Revision: D30903988
Pulled By: albanD
fbshipit-source-id: d6a74adb9e6d2f4be8ac707848ecabf06d629823
