python_setuptools3_rust: inherit ...build_meta

python_setuptools3_rust: inherit ...build_meta

Rather than inheriting the aging `setuptools3` bbclass, inherit
`python_setuptools_build_meta` which is one of the PEP 517 build
backends (for proper wheels using pyproject.toml).

Since python_setuptools_build_meta does not have a do_configure,
call the parent python_pep517_do_configure().

Signed-off-by: Tim Orling <tim.orling@konsulko.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>