KVM: x86: mmu: trace kvm_mmu_set_spte after the new SPTE was set

It makes more sense to print new SPTE value than the
old value.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220302102457.588450-1-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>