lib/test: introduce cpumask KUnit test suite

lib/test: introduce cpumask KUnit test suite

Add a basic suite of tests for cpumask, providing some tests for empty and
completely filled cpumasks.

Link: https://lkml.kernel.org/r/c96980ec35c3bd23f17c3374bf42c22971545e85.1656777646.git.sander@svanheule.net
Signed-off-by: Sander Vanheule <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Suggested-by: Yury Norov <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Marco Elver <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Valentin Schneider <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>