genirq: Consistently use '%u' format specifier for unsigned int variables

There are three cases in the genirq code when the irq, as an unsigned
integer variable, is converted to text representation by sprintf().
In two cases it uses '%d' specifier which is for signed values. While
it's not a problem right now, potentially it might be in the future
in case too big (> INT_MAX) number will appear there.

Consistently use '%u' format specifier for @irq which is declared as
unsigned int in all these cases.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250509154643.1499171-1-andriy.shevchenko@linux.intel.com