Remove unnecessary `view`s of `position_ids` (#26059)
* Remove unnecessary `view` of `position_ids` in `modeling_llama`
When `position_ids` is `None`, its value is generated using
`torch.arange`, which creates a tensor of size `(seq_length +
past_key_values_length) - past_key_values_length = seq_length`. The
tensor is then unsqueezed, resulting in a tensor of shape `(1,
seq_length)`. This means that the last `view` to a tensor of shape
`(-1, seq_length)` is a no-op.
This commit removes the unnecessary view.
* Remove no-op `view` of `position_ids` in rest of transformer models
