x86/kvm: Silence per-cpu pr_info noise about KVM clocks and steal time

I made the actual CPU bringup go nice and fast... and then Linux spends
half a minute printing stupid nonsense about clocks and steal time for
each of 256 vCPUs. Don't do that. Nobody cares.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20211209150938.3518-12-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>