pcmcia: cs: fix possible hung task and memory leak pccardd()
If device_register() returns error in pccardd(), it leads two issues:
1. The socket_released has never been completed, it will block
pcmcia_unregister_socket(), because of waiting for completion
of socket_released.
2. The device name allocated by dev_set_name() is leaked.
Fix this two issues by calling put_device() when device_register() fails.
socket_released can be completed in pcmcia_release_socket(), the name can
be freed in kobject_cleanup().