kernel: cxl/port: Fix use after free of parent_port in cxl_detach_ep()

In the Linux kernel, the following vulnerability has been resolved: cxl/port: Fix use after free of parentport in cxldetachep cxldetachep is called during bottom-up removal when all CXL memory devices beneath a switch port have been removed. For each port in the hierarchy it locks both the port a...