[PATCH] x86_64: interrupt array size should be aligned to NR_VECTORS

interrupt array is referred for idt vectors instead of NR_IRQS, so change size
to NR_VECTORS - FIRST_EXTERNAL_VECTOR. Also change to static.

Signed-off-by: Yinghai Lu <yinghai@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>