Use std::max_align_t rather than __attribute__((__aligned__)) to get max alignment
Use std::max_align_t rather than __attribute__((__aligned__)) to get max alignment

Summary: Because the former is standardized, and the latter is a syntax error under MSVC.

Reviewed By: yfeldblum

Differential Revision: D3672667

fbshipit-source-id: c0149b11367e36ba5574625240c41a167348199f

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