kunit: test: Drop CONFIG_MODULE ifdeffery

The function stubs exposed by module.h allow the code to compile properly
without the ifdeffery. The generated object code stays the same, as the
compiler can optimize away all the dead code.
As the code is still typechecked developer errors can be detected faster.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: David Gow <davidgow@google.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Link: https://lore.kernel.org/r/20250711-kunit-ifdef-modules-v2-3-39443decb1f8@linutronix.de
Signed-off-by: Daniel Gomez <da.gomez@samsung.com>

Author: t-8ch

lib/kunit/test.c

@@ -802,7 +802,6 @@ void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites)
 }
 EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
 
-#ifdef CONFIG_MODULES
 static void kunit_module_init(struct module *mod)
 {
 	struct kunit_suite_set suite_set, filtered_set;
@@ -890,7 +889,6 @@ static struct notifier_block kunit_mod_nb = {
 	.notifier_call = kunit_module_notify,
 	.priority = 0,
 };
-#endif
 
 KUNIT_DEFINE_ACTION_WRAPPER(kfree_action_wrapper, kfree, const void *)
 
@@ -981,20 +979,14 @@ static int __init kunit_init(void)
 	kunit_debugfs_init();
 
 	kunit_bus_init();
-#ifdef CONFIG_MODULES
 	return register_module_notifier(&kunit_mod_nb);
-#else
-	return 0;
-#endif
 }
 late_initcall(kunit_init);
 
 static void __exit kunit_exit(void)
 {
 	memset(&kunit_hooks, 0, sizeof(kunit_hooks));
-#ifdef CONFIG_MODULES
 	unregister_module_notifier(&kunit_mod_nb);
-#endif
 
 	kunit_bus_shutdown();