cxl/pci: Fix debug message in cxl_probe_regs()

Indicator string for mbox and memdev register set to status
incorrectly in error message.

Cc: <stable@vger.kernel.org>
Fixes: 30af9729 ("cxl/pci: Map registers based on capabilities")
Signed-off-by: Li Qiang (Johnny Li) <johnny.li@montage-tech.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163072205089.2250120.8103605864156687395.stgit@dwillia2-desk3.amr.corp.intel.com


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