nested vmx: Use a list to store the launched vvmcs for L1 VMM

nested vmx: Use a list to store the launched vvmcs for L1 VMM

Originally we use a virtual VMCS field to store the launch state of
a certain vmcs. However if we introduce VMCS shadowing feature, this
virtual VMCS should also be able to load into real hardware,
and VMREAD/VMWRITE operate invalid fields.

The new approach is to store the launch state into a list for L1 VMM.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Acked-by Eddie Dong <eddie.dong@intel.com>
Committed-by: Jan Beulich <jbeulich@suse.com>