irq_domain: fix type mismatch in debugfs output format

sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int.  On 64 bit platforms this causes a type mismatch:

    linux/kernel/irq/irqdomain.c:575: warning: field width should have type
    'int', but argument 6 has type 'long unsigned int'

This change casts the size to an int so printf gets the right data type.
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>

kernel/irq/irqdomain.c

@@ -629,7 +629,8 @@ static int virq_debug_show(struct seq_file *m, void *private)
 	int i;
 
 	seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
-		      "chip name", 2 * sizeof(void *) + 2, "chip data", "domain name");
+		      "chip name", (int)(2 * sizeof(void *) + 2), "chip data",
+		      "domain name");
 
 	for (i = 1; i < nr_irqs; i++) {
 		desc = irq_to_desc(i);