hwrng: core - remove (un)register_miscdev()

These functions are redundant after commit 0daa7a0a ("hwrng: Avoid
manual device_create_file() calls").

Let's call misc_(de)register() directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/core.c

@@ -486,16 +486,6 @@ static struct attribute *rng_dev_attrs[] = {
 
 ATTRIBUTE_GROUPS(rng_dev);
 
-static void __exit unregister_miscdev(void)
-{
-	misc_deregister(&rng_miscdev);
-}
-
-static int __init register_miscdev(void)
-{
-	return misc_register(&rng_miscdev);
-}
-
 static int hwrng_fillfn(void *unused)
 {
 	size_t entropy, entropy_credit = 0; /* in 1/1024 of a bit */
@@ -709,7 +699,7 @@ static int __init hwrng_modinit(void)
 		return -ENOMEM;
 	}
 
-	ret = register_miscdev();
+	ret = misc_register(&rng_miscdev);
 	if (ret) {
 		kfree(rng_fillbuf);
 		kfree(rng_buffer);
@@ -726,7 +716,7 @@ static void __exit hwrng_modexit(void)
 	kfree(rng_fillbuf);
 	mutex_unlock(&rng_mutex);
 
-	unregister_miscdev();
+	misc_deregister(&rng_miscdev);
 }
 
 fs_initcall(hwrng_modinit); /* depends on misc_register() */