Remove manual bindings for linspace, logspace and full (#81378)
These functions are bound manually because their default dtype isn't
always the same as `torch.get_default_dtype()`. This was necessary
because the python binding codegen effectively translated
`ScalarType? dtype=None` to `ScalarType dtype=torch.get_default_dtype()`.
I've fixed the python bindings generator to correctly pass through
`None`, and thus we can safely remove the manual bindings.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/81378
Approved by: https://github.com/ngimel
