scripts/head-object-list: Remove x86 from the list

Now that x86 boot code is not hardcoded to the particular linking
order, remove x86 files from the list and let them be placed inside
the vmlinux according only to the linker script and linker
preferences.

Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230109170403.4117105-3-alexandr.lobakin@intel.com