Running the testsuite as root isn't really recommended.
But lets not make tests fail unnecessarily when running as root.
Similar to the arm64-linux/scalar fixes. Plus 32bit variants that
don't exist on arm64.
Pass really invalid arguments to setuid[32], setgid[32], acct, fchown[32].
Make setresgid[32], setresuid[32], setregid[32], setreuid[32] always succeed.