Remove AT_LINK_STYLE entirely. (#29729)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29729
It already errored when you built with CUDA/HIP support as no longer supported;
now I expunge it entirely. Along the way, I delete useless INTERFACE
libraries (which aren't used anywhere else in the cmake.)
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D18571167
Pulled By: ezyang
fbshipit-source-id: f88c73a16fad3b61eaa7745a2d15514c68704bec
