Add CI job for AVX2 builds. (#1723)
Add CI job for AVX2 builds. (#1723)

Summary: Pull Request resolved: https://github.com/facebookresearch/faiss/pull/1723

Reviewed By: mdouze

Differential Revision: D26814122

Pulled By: beauby

fbshipit-source-id: ef7ea57b497e314960319c695ea46f22de208054

facebookresearch/faiss,facebookresearch/faiss,facebookresearch/faiss,facebookresearch/faiss