x86: Print the hypervisor returned tsc_khz during boot

On an AMD-64 system the processor frequency that is printed during
system boot, may be different than the tsc frequency that was
returned by the hypervisor, due to the value returned from
calibrate_cpu.

For debugging timekeeping or other related issues it might be
better to get the tsc_khz value returned by the hypervisor.

The patch below now prints the tsc frequency that the VMware
hypervisor returned.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1252095219.12518.13.camel@ank32.eng.vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>