Enable working ROCm tests (#19169)
Summary:
Enable multi-GPU tests that work with ROCm 2.2. Have been run three times on CI to ensure stability.
While there, remove skipIfRocm annotations for tests that depend on MAGMA. They still skip but now for the correct reason (no MAGMA) to improve our diagnostics.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19169
Differential Revision: D14924812
Pulled By: bddppq
fbshipit-source-id: 8b88f58bba58a08ddcd439e899a0abc6198fef64