Previously we use unified vm_config.c for all scenarios and use MACROs
for each configuration items, then the initialization of vm_configs[]
becomes more complicated when definition of MACROs increase, so change
the coding style that all configurable items could be explicitly shown in
vm_configuration.c to make code more readable.
Tracked-On: #2291
Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>