executor: add boot arguments page to SYZOS layout

Introduce a dedicated page at X86_SYZOS_ADDR_BOOT_ARGS to pass
configuration data from the executor to the SYZOS guest. This will allow
dynamic adjustments to the guest environment, such as specifying memory
region sizes.

- Added `MEM_REGION_FLAG_REMAINING` to flag the last memory region, which
will consume the rest of the available guest memory.
- Defined `struct syzos_boot_args` to pass the memory region layout to the
guest.
- Modified `syzos_mem_regions`:
    - Reduced X86_SYZOS_ADDR_VAR_IDT size to 10 pages.
    - Inserted the new X86_SYZOS_ADDR_BOOT_ARGS region.
    - Added a final region with MEM_REGION_FLAG_REMAINING.
- Updated `setup_vm` to:
    - Calculate the size of the REMAINING region.
    - Populate the `syzos_boot_args` structure in the boot args page.
- Updated `setup_pg_table` to use the REMAINING flag to map the last region.

0 files changed, 0 insertions, 0 deletions