We know it is already after 2000. Use the year 2000 offset for both 32
and 64 bit, which removes ifdefs and the 1970 magic.

[ tglx@linutronix.de: remove 1970 magic, replace bogus commit message ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>