HV: init and sanitize acrn multiboot info

Initialize and sanitize a acrn specific multiboot info struct with current
supported multiboot1 in very early boot stage, which would bring below
benifits:

- don't need to do hpa2hva convention every time when refering boot_regs;

- panic early if failed to sanitize multiboot info, so that don't need to
  check multiboot info pointer/flags and panic in later boot process;

- keep most code unchanged when introduce multiboot2 support in future;

Tracked-On: #4419

Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/arch/x86/init.c

@@ -14,7 +14,7 @@
 #include <logmsg.h>
 #include <seed.h>
 #include <ld_sym.h>
-#include <vboot.h>
+#include <boot.h>
 
 /* Push sp magic to top of stack for call trace */
 #define SWITCH_TO(rsp, to)                                              \