Fix error message for a wrong fork CUDA (#23030)
Summary:
Fix https://github.com/pytorch/pytorch/issues/17357
Unblock 1.2 release.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23030
Differential Revision: D16368004
Pulled By: zhangguanheng66
fbshipit-source-id: 44b6977790ce768efa4777bae41d4b26dae5f288
