hotfix: increase precision of GPTQ/AWQ-Marlin

[danieldk]

What does this PR do?

Sync with upstream change that improves the precision of the 'global_reduce' algorithm from FP16 to FP32. This solves some reported generation quality issues.

There is a small regression in performance (Llama 3.1 8B):

Before GPTQ-Marlin fix:

| Step    | Batch Size | Average             | Lowest              | Highest             |
|---------|------------|---------------------|---------------------|---------------------|
| Prefill | 1          | 56.44 tokens/secs   | 56.09 tokens/secs   | 56.97 tokens/secs   |
|         | 2          | 110.64 tokens/secs  | 109.85 tokens/secs  | 111.07 tokens/secs  |
|         | 4          | 211.77 tokens/secs  | 209.87 tokens/secs  | 212.77 tokens/secs  |
|         | 8          | 243.95 tokens/secs  | 243.18 tokens/secs  | 244.58 tokens/secs  |
|         | 16         | 320.99 tokens/secs  | 319.94 tokens/secs  | 321.91 tokens/secs  |
|         | 32         | 370.34 tokens/secs  | 369.72 tokens/secs  | 370.91 tokens/secs  |
| Decode  | 1          | 82.48 tokens/secs   | 82.00 tokens/secs   | 82.76 tokens/secs   |
|         | 2          | 162.07 tokens/secs  | 161.52 tokens/secs  | 162.40 tokens/secs  |
|         | 4          | 318.82 tokens/secs  | 318.34 tokens/secs  | 319.60 tokens/secs  |
|         | 8          | 617.87 tokens/secs  | 616.30 tokens/secs  | 618.96 tokens/secs  |
|         | 16         | 1159.00 tokens/secs | 1155.31 tokens/secs | 1161.47 tokens/secs |
|         | 32         | 2005.69 tokens/secs | 2000.95 tokens/secs | 2010.29 tokens/secs |

After:

| Step    | Batch Size | Average             | Lowest              | Highest             |
|---------|------------|---------------------|---------------------|---------------------|
| Prefill | 1          | 55.66 tokens/secs   | 53.66 tokens/secs   | 56.63 tokens/secs   |
|         | 2          | 107.86 tokens/secs  | 105.06 tokens/secs  | 109.49 tokens/secs  |
|         | 4          | 205.86 tokens/secs  | 203.58 tokens/secs  | 207.39 tokens/secs  |
|         | 8          | 237.30 tokens/secs  | 235.50 tokens/secs  | 237.97 tokens/secs  |
|         | 16         | 314.34 tokens/secs  | 313.70 tokens/secs  | 315.10 tokens/secs  |
|         | 32         | 369.78 tokens/secs  | 369.21 tokens/secs  | 370.55 tokens/secs  |
| Decode  | 1          | 81.37 tokens/secs   | 80.71 tokens/secs   | 81.65 tokens/secs   |
|         | 2          | 160.10 tokens/secs  | 159.60 tokens/secs  | 160.53 tokens/secs  |
|         | 4          | 315.80 tokens/secs  | 315.15 tokens/secs  | 316.32 tokens/secs  |
|         | 8          | 612.87 tokens/secs  | 611.21 tokens/secs  | 614.92 tokens/secs  |
|         | 16         | 1154.18 tokens/secs | 1151.36 tokens/secs | 1157.41 tokens/secs |
|         | 32         | 1968.70 tokens/secs | 1964.30 tokens/secs | 1974.53 tokens/secs |

Upstream issue/PR:

vllm-project/vllm#6795

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[Narsil]

LGTM. Didn't check kernel given large modifications (most likely some autoformatter)

[danieldk]

Closing in favor of #2320.