Complete FastLinear.load parameters in OPTDecoder initialization (#1060)

# What does this PR do?

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`FastLinear.load` requires 4 parameters, but in the following only 3 are
given. This PR fix this.

```python
# server/text_generation_server/models/custom_modeling/opt_modeling.py
        if config.word_embed_proj_dim != config.hidden_size:
            self.project_out = FastLinear.load(
                config, prefix="model.decoder.project_out", bias=False
            )
        else:
            self.project_out = None

        if config.word_embed_proj_dim != config.hidden_size:
            self.project_in = FastLinear.load(
                config, prefix="model.decoder.project_in", bias=False
```

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server/text_generation_server/models/custom_modeling/opt_modeling.py

@@ -444,14 +444,14 @@ class OPTDecoder(OPTPreTrainedModel):
 
         if config.word_embed_proj_dim != config.hidden_size:
             self.project_out = FastLinear.load(
-                config, prefix="model.decoder.project_out", bias=False
+                config, prefix="model.decoder.project_out", weights=weights, bias=False
             )
         else:
             self.project_out = None
 
         if config.word_embed_proj_dim != config.hidden_size:
             self.project_in = FastLinear.load(
-                config, prefix="model.decoder.project_in", bias=False
+                config, prefix="model.decoder.project_in", weights=weights, bias=False
             )
         else:
             self.project_in = None