lib/test_cpumask: Add for_each_cpu_and(not) tests

Following the recent introduction of for_each_andnot(), add some tests to
ensure for_each_cpu_and(not) results in the same as iterating over the
result of cpumask_and(not)().

Suggested-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Valentin Schneider <vschneid@redhat.com>