Previously the load GPA of LaaG boot params like zeropage/cmdline and
initgdt are all hard-coded, this would bring potential LaaG boot issues.
The patch will try to fix this issue by finding a 32KB load_params memory
block for LaaG to store these guest boot params.
For other guest with raw image, in general only vgdt need to be cared of so
the load_params will be put at 0x800 since it is a common place that most
guests won't touch for entering protected mode.
Tracked-On: #5626
Signed-off-by: Victor Sun <victor.sun@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>