Change TH_BLAS_MKL into AT_MKL_ENABLED() (#70219)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/70219
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69419
Test Plan: Imported from OSS
Reviewed By: malfet
Differential Revision: D33246758
Pulled By: ngimel
fbshipit-source-id: aedef4c9ef97b6aa9f574313c94f774b77df2748
