Delete more code from __init__.py as we'll never be running from inside
a build tree.
Replace the use of skbuild.setup() with setuptools.setup(): the same
Python module is built and the only value-add is the potential build of
ninja, which we don't want and delete anyway.
This means we can remove most of the DEPENDS and RDEPENDS.
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
