Use @skipIfNoFBGEMM instead of direct check (#39068)
Summary:
Should be a no-op, just makes the intent a bit cleaner
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39068
Differential Revision: D21829464
Pulled By: malfet
fbshipit-source-id: dc174a3d7da3701bd9d31c366dfa9d24044ef27a
