vulkan: add LOG operation support for F32 and F16

[zayac]

Summary

Implements LOG operation for the Vulkan backend with F32 and F16 support.

Part of #14909.

Testing

./build/bin/test-backend-ops -o LOG
ggml_vulkan: Found 1 Vulkan devices:
ggml_vulkan: 0 = NVIDIA GeForce RTX 5070 (NVIDIA) | uma: 0 | fp16: 1 | bf16: 1 | warp size: 32 | shared memory: 49152 | int dot: 1 | matrix cores: NV_coopmat2
Testing 2 devices

Backend 1/2: Vulkan0
  Device description: NVIDIA GeForce RTX 5070
  Device memory: 12227 MB (10998 MB free)

  LOG(type=f16,ne=[10,5,4,3]): OK
  LOG(type=f16,ne=[7,1,5,3]): OK
  LOG(type=f32,ne=[10,5,4,3]): OK
  LOG(type=f32,ne=[7,1,5,3]): OK
  4/4 tests passed
  Backend Vulkan0: OK
Backend 2/2: CPU
  Skipping CPU backend
2/2 backends passed
OK

[zayac]

Thanks, Jeff, for the feedback. I addressed all the comments. PTAL.

[zayac]

Hi @0cc4m, could you please review / approve this PR?

[0cc4m]

Someone has updated the same line in ops.md, so there's another conflict, sorry. I'll merge once you rebase it again.

[zayac]

Someone has updated the same line in ops.md, so there's another conflict, sorry. I'll merge once you rebase it again.

Should be good now. Please merge as fast as possible :)

[CISC]

Was this supposed to happen? https://github.com/ggml-org/llama.cpp/actions/runs/19414817156/job/55541539280

[0cc4m]

No, I think that's another RTE issue. It didn't happen on my hardware, but seems persistent on the CI.

[zayac]

I can neither reproduce it locally.

Both

./build/bin/test-backend-ops test -o LOG
./build/bin/test-backend-ops test -b Vulkan0

succeed for me.

[0cc4m]

Let's see if #17320 fixes it.