Fix broken IsVTXDisabled detection on AMD CPU
Fix broken IsVTXDisabled detection on AMD CPU

VMX is in FeatureNames, but SVM is in ExtraFeatureNames
This meant that detection *always* failed for SVM (AMD)

Thanks to user @hilbertxia

Signed-off-by: Anders F Björklund <c6169fcaa665ed956024051b5047d142d4ac3fe5@gmail.com>

docker/machine,docker/machine,dweomer/docker-machine,dweomer/docker-machine