HV: re-arch boot component header

The patch re-arch boot component header files by:

- moving multiboot.h from include/arch/x86/ to boot/include/ and keep
  this header for multiboot1 protocol data struct only;

- moving multiboot related MACROs in cpu_primary.S to multiboot.h;

- creating an independent boot.h to store acrn specific boot information
  for other files' reference;

Tracked-On: #4419

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

hypervisor/boot/guest/vboot_wrapper.c

@@ -4,11 +4,11 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#include <multiboot.h>
 #include <vm.h>
 #include <types.h>
 #include <pgtable.h>
 #include <acpi.h>
+#include <boot.h>
 #include <vboot.h>
 #include <direct_boot.h>
 #include <deprivilege_boot.h>