kunit: debugfs: Fix unchecked dereference in debugfs_print_results()

Move the call to kunit_suite_has_succeeded() after the check that
the kunit_suite pointer is valid.

This was found by smatch:

 lib/kunit/debugfs.c:66 debugfs_print_results() warn: variable
 dereferenced before check 'suite' (see line 63)
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 38289a26 ("kunit: fix debugfs code to use enum kunit_status, not bool")
Reviewed-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/debugfs.c

@@ -60,12 +60,14 @@ static void debugfs_print_result(struct seq_file *seq, struct string_stream *log
 static int debugfs_print_results(struct seq_file *seq, void *v)
 {
 	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
-	enum kunit_status success = kunit_suite_has_succeeded(suite);
+	enum kunit_status success;
 	struct kunit_case *test_case;
 
 	if (!suite)
 		return 0;
 
+	success = kunit_suite_has_succeeded(suite);
+
 	/* Print KTAP header so the debugfs log can be parsed as valid KTAP. */
 	seq_puts(seq, "KTAP version 1\n");
 	seq_puts(seq, "1..1\n");