[Core] Support loading GGUF model (#5191)

Co-authored-by: Michael Goin <michael@neuralmagic.com>

tests/quantization/test_lm_head.py

@@ -7,11 +7,12 @@ from typing import Tuple
 import pytest
 import torch
 
-from vllm.model_executor.layers.linear import UnquantizedLinearMethod
 from vllm.model_executor.layers.quantization.gptq import GPTQLinearMethod
 from vllm.model_executor.layers.quantization.gptq_marlin import (
     GPTQMarlinLinearMethod)
 from vllm.model_executor.layers.quantization.marlin import MarlinLinearMethod
+from vllm.model_executor.layers.vocab_parallel_embedding import (
+    UnquantizedEmbeddingMethod)
 
 PROMPT = "On the surface of Mars, we found"
 
@@ -37,7 +38,8 @@ def test_lm_head(
             lm_head_layer.linear_method,
             (GPTQLinearMethod, GPTQMarlinLinearMethod, MarlinLinearMethod))
     else:
-        assert isinstance(lm_head_layer.linear_method, UnquantizedLinearMethod)
+        assert isinstance(lm_head_layer.linear_method,
+                          UnquantizedEmbeddingMethod)
 
     print(
         vllm_model.generate_greedy(prompts=["Hello my name is"],