cxl/port: Use __free() to drop put_device() for cxl_port

cxl/port: Use __free() to drop put_device() for cxl_port

Using scope-based resource management __free() marco with a new helper
called put_cxl_port() to drop open coded the put_device() used to
dereference the 'struct device' in cxl_port.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Li Ming <ming4.li@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://patch.msgid.link/20240830013138.2256244-1-ming4.li@intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>