genirq/irqdesc: Use sysfs_emit() to instead of s*printf()

Follow the advice of the Documentation/filesystems/sysfs.rst that show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the value
to be returned to user space.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250416101651.2128688-1-andriy.shevchenko@linux.intel.com