The sos_vm config under arch/x86/configs/$(CONFIG_BOARD) folder should be
customer specific configuration, leave it back to customer.
When hypervisor start building, it will check whether BOARD specific sos_vm.h
exist in configs/$(CONFIG_BOARD) folder. If exist, then include this header;
if not, then include default sos_vm config header under configs/default folder.
Tracked-On: #2291
Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>