cxl/mem: Disable cxl device power management

There is no power management of cxl virtual devices, disable
device-power-management and runtime-power-management to prevent
userspace from growing expectations of those attributes appearing. They
can be added back in the future if needed.

Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/161728761025.2474381.808344500111924819.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/cxl/mem.c

@@ -1203,6 +1203,7 @@ static struct cxl_memdev *cxl_memdev_alloc(struct cxl_mem *cxlm)
 	dev->bus = &cxl_bus_type;
 	dev->devt = MKDEV(cxl_mem_major, cxlmd->id);
 	dev->type = &cxl_memdev_type;
+	device_set_pm_not_required(dev);
 
 	cdev = &cxlmd->cdev;
 	cdev_init(cdev, &cxl_memdev_fops);