kvm-unit-tests: nSVM: Test that CR0[63:32] are not set on VMRUN of nested guests

According to section "Canonicalization and Consistency Checks" in APM vol. 2,
the following guest state is illegal:

	"CR0[63:32] are not zero."

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20200420225825.3184-2-krish.sadhukhan@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>