update masked fill inplace version docs

docs/guides/model_convert/convert_from_pytorch/api_difference/Tensor/torch.Tensor.masked_fill_.md

@@ -0,0 +1,22 @@
+## [ 参数完全一致 ] torch.Tensor.masked_fill_
+
+### [torch.Tensor.masked_fill_](https://pytorch.org/docs/stable/generated/torch.Tensor.masked_fill_.html?highlight=masked_fill_#torch.Tensor.masked_fill_)
+
+```python
+torch.Tensor.masked_fill_(mask, value)
+```
+
+### [paddle.Tensor.masked_fill_]()
+
+```python
+paddle.Tensor.masked_fill_(mask, value, name=None)
+```
+
+两者功能一致，参数完全一致，具体如下：
+
+### 参数映射
+
+| PyTorch | PaddlePaddle | 备注                                               |
+|---------|--------------| -------------------------------------------------- |
+| mask     | mask          | 布尔张量，表示要填充的位置    |
+| value     | value          | 用于填充目标张量的值    |