security/keys: make big_key.c explicitly non-modular

The Kconfig currently controlling compilation of this code is:

config BIG_KEYS
        bool "Large payload keys"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag since all that information
is already contained at the top of the file in the comments.

Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David Howells <dhowells@redhat.com>

security/keys/big_key.c

@@ -9,7 +9,6 @@
  * 2 of the Licence, or (at your option) any later version.
  */
 
-#include <linux/module.h>
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/file.h>
@@ -18,8 +17,6 @@
 #include <keys/user-type.h>
 #include <keys/big_key-type.h>
 
-MODULE_LICENSE("GPL");
-
 /*
  * Layout of key payload words.
  */
@@ -212,18 +209,8 @@ long big_key_read(const struct key *key, char __user *buffer, size_t buflen)
 	return ret;
 }
 
-/*
- * Module stuff
- */
 static int __init big_key_init(void)
 {
 	return register_key_type(&key_type_big_key);
 }
-
-static void __exit big_key_cleanup(void)
-{
-	unregister_key_type(&key_type_big_key);
-}
-
-module_init(big_key_init);
-module_exit(big_key_cleanup);
+device_initcall(big_key_init);