Support cuda 11.5: install magma for cuda in conda (#68665)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/68667
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68665
Reviewed By: malfet
Differential Revision: D32570283
Pulled By: atalman
fbshipit-source-id: 4471fe8c4f8cc74c542ed67038322f07e861af73
