KVM: nVMX: Add a TSC multiplier field in VMCS12

This is required for supporting nested TSC scaling.

Signed-off-by: Ilias Stamatis <ilstam@amazon.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210526184418.28881-6-ilstam@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>