fix: remove broken hc_head warmup (wrong tensor shape)

hc_head_fuse_tilelang expects fn shape[0]=hc_mult (4) but we passed
hc_mult*(2+hc_mult) (24). Since --enforce-eager disables @torch.compile
anyway, hc_head runs eagerly and doesn't need warmup.

vllm/patches/deepseek_v4.py

@@ -2276,29 +2276,8 @@ class DeepseekV4ForCausalLM(nn.Module):
         except Exception as e:
             print(f"    mhc_post warmup failed (non-fatal): {e}", flush=True)
 
-        # Warmup hc_head (also @torch.compile lazy)
-        try:
-            from vllm.platforms import current_platform
-            hc_head_fn = torch.randn(
-                hc_mult * (2 + hc_mult), hc_mult * hidden_size,
-                dtype=torch.float32, device=device)
-            hc_head_scale = torch.randn(3, dtype=torch.float32, device=device)
-            hc_head_base = torch.randn(
-                hc_mult * (2 + hc_mult), dtype=torch.float32, device=device)
-            hs = torch.randn(1, hc_mult, hidden_size, dtype=torch.bfloat16,
-                             device=device)
-            hc_head(hs, hc_head_fn, hc_head_scale, hc_head_base,
-                    config.rms_norm_eps, config.hc_eps)
-            print("    hc_head ✓", flush=True)
-        except Exception as e:
-            print(f"    hc_head warmup failed (non-fatal): {e}", flush=True)
-
         # Free dummy tensors
         del residual, fn, hc_scale, hc_base, x, post_mix, comb_mix
-        try:
-            del hc_head_fn, hc_head_scale, hc_head_base, hs
-        except NameError:
-            pass
         torch.cuda.empty_cache()
 
     def get_expert_mapping(self) -> list[tuple[str, str, int, str]]: