…rnels (#165815)

Scheduler relies on node.last_usage to free buffers. `last_usage` may contain a buffer that is allocated in previous graph partition AND not directly accessed in the current graph partition.

## Example
```python
def f(x):
    y = x + 1
    z = torch.ops.aten.view.dtype(y, torch.float8_e4m3fn)
    z_cpu = z.cpu()
    u_cuda = z_cpu.cuda()
    return u_cuda
```

In the generated code, we have
```
def partition_0(args):
    ...
    # Topologically Sorted Source Nodes: [y, z], Original ATen: [aten.add, aten.view]
    buf1 = torch.ops.aten.view.dtype(buf0, torch.float8_e4m3fn) # < ------ buf1 is a view of buf0
    buf2 = buf1 # <------- buf2 is buf1
    assert_size_stride(buf2, (8, ), (1, ), 'torch.ops.aten.view.dtype')
    assert_alignment(buf2, 16, 'torch.ops.aten.view.dtype')
    return (buf2, )

def call(self, args):
    ...
    (buf2,) = self.partitions[0](partition0_args)
    ...
    buf3.copy_(buf2, False)
    del buf0
    del buf1
    del buf2  # <---- `del buf2` leads to `del buf0`. BUT `buf0` is not returned from partition_0.
    ...
```

Note: view is treated as a fallback kernel due to its special dtype.
https://github.com/pytorch/pytorch/blob/de09bab4b66002a8a9a2195f50f96a78868a3d39/torch/_inductor/lowering.py#L841-L843

## Fix

This PR fixes the issue by also returning these buffers to be freed later.

Pull Request resolved: #165815
Approved by: https://github.com/eellison

(cherry picked from commit 1891239)