kobject: convert kernel_kset to be a kobject

kernel_kset does not need to be a kset, but a much simpler kobject now
that we have kobj_attributes.

We also rename kernel_kset to kernel_kobj to catch all users of this
symbol with a build error instead of an easy-to-ignore build warning.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/configfs/mount.c b/fs/configfs/mount.c
index c4ee7f0..54bf0db 100644
--- a/fs/configfs/mount.c
+++ b/fs/configfs/mount.c
@@ -140,7 +140,7 @@
 	if (!configfs_dir_cachep)
 		goto out;
 
-	config_kobj = kobject_create_and_add("config", &kernel_kset->kobj);
+	config_kobj = kobject_create_and_add("config", kernel_kobj);
 	if (!config_kobj) {
 		kmem_cache_destroy(configfs_dir_cachep);
 		configfs_dir_cachep = NULL;