[IA64] Don't go beyond iosapic_intr_info's arraysize

vi arch/ia64/kernel/iosapic.c +142
static struct iosapic_intr_info {
	...
} iosapic_intr_info[NR_IRQS];

But at line 510 we have:
	for (i = 0; i <= NR_IRQS; i++) {

s/<=/</

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>