Make IQ1_M work for QK_K = 64

[ikawrakow]

As with all other i-quants, AVX2, ARM_NEON, CPU scalar, Metal. CUDA will come later.

[ikawrakow]

@ggerganov Perhaps you should disable the nix build? I don't know about you, but for me a check running for 6 hours and eventually cancelled on every commit does not make much sense. If nothing else, lets have some merci with our planet.

[ggerganov]

@SomeoneSerge Is there something to be done to speed-up the builds? AFAICT, with the recent workflow concurrency changes (#6243) all Nix builds are bound to be cancelled since the chance of committing something to master within 6h is quite large and this would cancel all running workflows

[SomeoneSerge]

@ggerganov thanks for the heads-up; I noticed a few cancelled builds but haven't got around to investigate this. I opened a tracking issue for now: #6346

[mscheong01]

If we don't want nix builds to fail on master, we could exempt the master branch as stated in the #6243 description

But, if we don't want this to happen with our master branch workflows, we can make an exception. Here's how we could set it up:

concurrency: 
  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.event.inputs.sha }}
  cancel-in-progress: true