[minor] Fix undefined variable (#45246)
Summary:
The commit https://github.com/pytorch/pytorch/commit/2a37f3fd2f74e2d10f3440e6dfef2d5389caab62 https://github.com/pytorch/pytorch/pull/45130 deleted the python variable `capability` which is used in later lines.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/45246
Reviewed By: walterddr
Differential Revision: D23923916
Pulled By: malfet
fbshipit-source-id: c5d7fef9e4a87ccc621191200e5965710e9d6aaa
