weight is on the meta device, we need a `value` to put it in 0 when convert Qwen2-0.5B

I have successfully SFTed Qwen2-0.5B using XTuner. When I convert the qlora checkpoint to hf, `weight is on the meta device, we need a `value` to put it in 0` occurs.

convert command
```
CUDA_VISIBLE_DEVICES=0 xtuner convert pth_to_hf qwen2_config qwen2_checkpoint qwen2_res
```

### Environment
- GPU: V100
- XTuner: 0.1.21
- CUDA: 11.8