x86: vmx: Test INIT processing during various CPU VMX states

Add vmx test to verify the functionality introduced by KVM commit:
4b9852f4f389 ("KVM: x86: Fix INIT signal handling in various CPU states").

The test verifies the following functionality:
1) An INIT signal received when CPU is in VMX operation
   is blocked until it exits VMX operation.
2) If there is an INIT signal pending when CPU is in
   VMX non-root mode, it result in VMExit with (reason == 3).
3) Exit from VMX non-root mode on VMExit do not clear
   pending INIT signal in LAPIC.
4) When CPU exits VMX operation, pending INIT signal in
   LAPIC is processed.

Note: The test is excluded from the "vmx" test-suite as
it ruins the execution environment of CPU1 because
during the test it process an INIT signal.

Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>