drivers/base/memory: add memory block to memory group after registration succeeded

drivers/base/memory: add memory block to memory group after registration succeeded

If register_memory() fails, we freed the memory block but already added
the memory block to the group list, not good.  Let's defer adding the
block to the memory group to after registering the memory block device.

We do handle it properly during unregister_memory(), but that's not
called when the registration fails.

Link: https://lkml.kernel.org/r/20220128144540.153902-1-david@redhat.com
Fixes: 028fc57a1c36 ("drivers/base/memory: introduce "memory groups" to logically group memory blocks")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>