[PATCH v2 0/3] Improvements to x86 boot code

[Andrew Cooper <andrew.cooper3@citrix.com>]

These patches are ones I have had since working on c/s 1ed76797439e "x86/boot:
fix BIOS memory corruption on certain IBM systems" in the 4.4 freeze window,
which required frequent reference to the disassembly.

The early code uses mixed processor modes and objdump doesn't know when to
change between them.  It can be overridden to an appropriate mode for the boot
code using -M options, but symbol tracking becomes broken.  I ended up
referencing the 64, 32 and 16 bit disassemblies side by side; one with correct
symbols and two with correct instructions.  This series was started to remove
extraneous clutter from the text disassembly.

Patch 1 moves some data from .init.text to .init.data
Patch 2 moves some code and data from .text to .init.text and .init.data
Patch 3 adds hlt instructions to terminal loops

Updates in v2:
 * Drop original patch 1 as it is now committed
 * init.data -> init.rodata
 * Fix missing @progbits
 * .Lhalt label for long jump
 * Align gdt_boot_descr

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Keir Fraser <keir@xen.org>
CC: Jan Beulich <JBeulich@suse.com>