[XPU][Graph] Replace boolean-mask assignment with torch.where (#60529)

Signed-off-by: zhenwei-intel <zhenwei.liu@intel.com>
Co-authored-by: Kunshang Ji <kunshang.ji@intel.com>

vllm/model_executor/models/mimo_mtp.py

@@ -73,7 +73,7 @@ class MiMoMultiTokenPredictorLayer(nn.Module):
     ) -> torch.Tensor:
         assert inputs_embeds is not None
         # masking inputs at position 0, as not needed by MTP
-        inputs_embeds[positions == 0] = 0
+        inputs_embeds = torch.where(positions.unsqueeze(-1) == 0, 0, inputs_embeds)
         inputs_embeds = self.token_layernorm(inputs_embeds)
         previous_hidden_states = self.hidden_layernorm(previous_hidden_states)