list: test: remove unused struct 'klist_test_struct'

'klist_test_struct' has been unused since the original
commit 57b4f760 ("list: test: Test the klist structure").

Remove it.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/list-test.c

@@ -1201,12 +1201,6 @@ static struct kunit_suite hlist_test_module = {
 };
 
 
-struct klist_test_struct {
-	int data;
-	struct klist klist;
-	struct klist_node klist_node;
-};
-
 static int node_count;
 static struct klist_node *last_node;