device property: Drop 'test' prefix in parameters of fwnode_is_ancestor_of()

The part 'is' in the function name implies the test against something.
Drop unnecessary 'test' prefix in the fwnode_is_ancestor_of() parameters.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>