move to non-legacy magma v2 headers (#49978)
Summary:
We recently (https://github.com/pytorch/pytorch/issues/7582) dropped magma v1 support, but we were still including the legacy compatibility headers and using functions only provided by them.
This changes the includes to the new magma_v2 header and fixes the triangular solve functions to use the v2-style magma_queue-using API.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/49978
Reviewed By: mrshenli
Differential Revision: D25752499
Pulled By: ngimel
fbshipit-source-id: 26d916bc5ce63978b341aefb072af228f140637d
