rune/libenclave/skeleton && sgx-tools: Resolve the launch token adaptation problem on sgx2 + in-tree

- sgx-tools gen-token command reports an error when running on machine with FLC
- Operations related to lanunch token are not supported on machine with FLC

Signed-off-by: Shirong Hao shirong@linux.alibaba.com

Signed-off-by: NShirong Hao <shirong@linux.alibaba.com>

Xfrm needs support the same xsave feature in encalve as in OS.
By cpuid, it can get the same value between xfrm and xcr0.
Signed-off-by: NLiang Yang <liang3.yang@intel.com>
Reviewed-by: Jia Zhang <zhang.jia@linux.alibaba.com>