cxl/pci: Use correct flag for sanitize polling

This is a bogus value, left behind from a previous version.

Fixes: 0c36b6ad ("cxl/mbox: Add sanitization handling machinery")
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/7q3vcjqidtmxmys4n34g6b3mygvhaen7yikzxanpz56lw43fz7@7subbtbfkmyx


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