cxl/pci: Fix potential bogus return value upon successful probing

If cxl_pci_ras_unmask() returns non-zero, cxl_pci_probe() will end up
returning that value, instead of zero.

Fixes: 248529ed ("cxl: add RAS status unmasking for CXL")
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://patch.msgid.link/20241115170032.108445-1-dave@stgolabs.net


Signed-off-by: Dave Jiang <dave.jiang@intel.com>