Staging: pohmelfs: avoid null dereference

err_out_put is for when the netfs_trans_alloc() succeeded.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>