nVMX x86: APIC virtual controls must be unset if "Use TPR shadow" is unset

According to section "Checks on VMX Controls" in Intel SDM vol 3C, the
following check needs to be enforced on vmentry of L2 guests:

    If the "use TPR shadow" VM-execution control is 0, the following
    VM-execution controls must also be 0: "virtualize x2APIC mode",
    "APIC-register virtualization" and "virtual-interrupt delivery".

This unit-test validates the above vmentry check.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>