x86 bootstrap features

[Emmanuel Dreyfus <manu%netbsd.org@localhost>]

Hello

I recently added features to x86 bootstraps (GPT and RAIDframe support,
multiboot 2), which caused the files to grow. That causes troubles:

- I had to disable multiboot 2 for dosboot, otherwise the binary gets too
  big and the build fails.
- In kern/54560, it seems we discovered pxeboot_ia32.bin should not get
  bigger than 64 kB. We will have to disable multiboot 2 there too to 
  keep below 64 kB.

The other boostraps where multiboot 2 is present are boot, efiboot and
netboot. It is desirable for the two formers, but I am less convinced
for the later.

Generally speaking, does anyone see any usage fpr GPT and RAIDframe
support, or multiboot 2 support for dosboot, pxeboot and netboot? If
not, we could disable the features for that boostraps, which would
save space for later.

And last question; should we have a build-time check that pxeboot_ia32.bin
is smaller than 64 kB?

-- 
Emmanuel Dreyfus
manu%netbsd.org@localhost