If sgx is supported in guest, present SGX capabilities to guest.
There will be only one EPC section presented to guest, even if EPC
memory for a guest is from muiltiple physcial EPC sections.
Tracked-On: #3179
Signed-off-by: Binbin Wu <binbin.wu@intel.com>
Reviewed-by: Yan, Like <like.yan@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>