oneDNN: compile without -msse4.1

[danieldk]

Motivation for this change

Follow-up to #93692. I think I have found the culprit. According to

https://logs.nix.samueldr.com/nixos-dev/2019-03-09#2025618;

ike is a 6100 series Opteron, which does not support SSE 4.1:

https://en.wikipedia.org/wiki/List_of_AMD_Opteron_microprocessors#Opteron_6100-series_%22Magny-Cours%22_(45_nm)

oneDNN adds -msse4.1 by default. This PR removes architecture optimization flags.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[marsam]

@danieldk thanks for following up on this

[danieldk]

Hmpf. We seem to get further, but still no dice:

https://hydra.nixos.org/build/124427154/nixlog/1

Now 9/101 tests fail. It seems that OneDNN is really not tested by upstream on machines without SSE4.1. The problem is that every time this gets built on ike (or another older Hydra machine), the build fails along with all dependencies with long build times, such as PyTorch. Maybe we should consider disabling tests @bhipple @alexarice ?