printf: add tests for generic FourCCs

This patch adds support for kunit tests of generic 32-bit FourCCs added to
vsprintf.

Acked-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Aditya Garg <gargaditya08@live.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/PN3PR01MB95973AF4F6262B2D1996FB25B8B52@PN3PR01MB9597.INDPRD01.PROD.OUTLOOK.COM


Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>