[PATCH] x86_64 irq: Remove unnecessary irq 0 setup.

The code in io_apic.c and in i8259.c currently hardcode the same
vector for the timer interrupt so there is no reason for a special
assignment for the timer as the setup for the i8259 already takes care
of this.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>