Fix composite compliance problems for linalg.{matrix_power, inv, cholesky} (#69437)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69437
linalg.{inv, cholesky} are problematic because they call .data_ptr().
This makes them not composite compliant (e.g. meta tensors will not run
on them correctly). This PR makes them composite compliant by adding a
new native_functions operator that does error checking,
`_linalg_check_errors(Tensor info, str api_name, bool is_matrix`
that is a primitive with respect to autograd.
This PR modifies linalg.inv and linalg.cholesky to call the new error
check function. I also needed to refactor singleCheckErrors and
batchCheckErrors to accept a c10::string_view instead of a
`const char*`; you can convert `const char*` to c10::string_view but not
the other way around because `string_view` does not require null
terminated buffers.
Finally, there is a bugfix in `__torch_dispatch__` for this PR for
the composite compliant testing mechanism. Previously,
`__torch_dispatch__` could not handle operators with no returns; this PR
fixes that. No returns in C++ is equivalent to a single None return in
Python.
Test Plan: - composite compliant tests
Reviewed By: albanD
Differential Revision: D32883666
Pulled By: zou3519
fbshipit-source-id: d5a3f52ebab116c93e1a54a203eacc8f787de7e2
(cherry picked from commit 9e24c9599a043877ab4f289469be55550c996a79)
