Instead of duplicating logic, we can use the run.sh that the test suite
installs.
Unless told otherwise, the util-linux test suite assumes that it is
running in a build tree and looks for binaries to run, but we're on
target so pass --use-system-commands (drops ~180 skips to tens).
Add --show-diff so that debugging can be done from the logs alone.
Remove redundant path manipulation that is now done upstream.
If PAM is disabled, delete the chfn test: it will run the chfn from
shadow which has different output, and the test will fail.
[ YOCTO #14244 ]
Signed-off-by: Ross Burton <ross.burton@arm.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
