kunit: test: Log the correct filter string in executor_test

KUnit's executor_test logs the filter string in KUNIT_ASSERT_EQ_MSG(),
but passed a random character from the filter, rather than the whole
string.

This was found by annotating KUNIT_ASSERT_EQ_MSG() to let gcc validate
the format string.

Fixes: 76066f93 ("kunit: add tests for filtering attributes")
Signed-off-by: David Gow <davidgow@google.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/executor_test.c

@@ -129,7 +129,7 @@ static void parse_filter_attr_test(struct kunit *test)
 			GFP_KERNEL);
 	for (j = 0; j < filter_count; j++) {
 		parsed_filters[j] = kunit_next_attr_filter(&filter, &err);
-		KUNIT_ASSERT_EQ_MSG(test, err, 0, "failed to parse filter '%s'", filters[j]);
+		KUNIT_ASSERT_EQ_MSG(test, err, 0, "failed to parse filter from '%s'", filters);
 	}
 
 	KUNIT_EXPECT_STREQ(test, kunit_attr_filter_name(parsed_filters[0]), "speed");