[XPU] fix pos_emb_type bug (#4638)

Author: cqulilujia

fastdeploy/worker/xpu_model_runner.py

@@ -850,7 +850,7 @@ def _init_share_inputs(self, max_num_seqs: int):
             else:  # neox style = False
                 rope_head_dim = head_dim // 2
 
-            if head_dim == self.model_config.head_dim:
+            if rope_head_dim == self.model_config.head_dim:
                 self.share_inputs["pos_emb_type"] = "NORMAL"
             else:
                 self.share_inputs["pos_emb_type"] = "HALF_HEAD_DIM"