Refactor the handling of unsupported eVMCS to use a 2-d array to store
the set of unsupported controls.  KVM's handling of eVMCS is completely
broken as there is no way for userspace to query which features are
unsupported, nor does KVM prevent userspace from attempting to enable
unsupported features.  A future commit will remedy that by filtering and
enforcing unsupported features when eVMCS, but that needs to be opt-in
from userspace to avoid breakage, i.e. KVM needs to maintain its legacy
behavior by snapshotting the exact set of controls that are currently
(un)supported by eVMCS.

No functional change intended.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[sean: split to standalone patch, write changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-8-vkuznets@redhat.comSigned-off-by: Paolo Bonzini <pbonzini@redhat.com>