cxl/test: Add Sanitize opcode support

Add support to emulate the "Sanitize" operation, without
incurring in the background.

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230612181038.14421-6-dave@stgolabs.net


Signed-off-by: Dan Williams <dan.j.williams@intel.com>