security/integrity: remove unnecessary 'init_keyring' variable

The 'init_keyring' variable actually just gave the value of
CONFIG_INTEGRITY_TRUSTED_KEYRING.  We should check the config option
directly instead.  No change in behavior; this just simplifies the code.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

security/integrity/digsig.c

@@ -37,12 +37,6 @@ static const char * const keyring_name[INTEGRITY_KEYRING_MAX] = {
 	"_module",
 };
 
-#ifdef CONFIG_INTEGRITY_TRUSTED_KEYRING
-static bool init_keyring __initdata = true;
-#else
-static bool init_keyring __initdata;
-#endif
-
 #ifdef CONFIG_IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY
 #define restrict_link_to_ima restrict_link_by_builtin_and_secondary_trusted
 #else
@@ -85,7 +79,7 @@ int __init integrity_init_keyring(const unsigned int id)
 	struct key_restriction *restriction;
 	int err = 0;
 
-	if (!init_keyring)
+	if (!IS_ENABLED(CONFIG_INTEGRITY_TRUSTED_KEYRING))
 		return 0;
 
 	restriction = kzalloc(sizeof(struct key_restriction), GFP_KERNEL);