HOWTO cross-build m68k linux-image

Building linux-image packages takes a while, especially on the "slower
arches", ie m68k. Cross-compiling is an alternative, and it works very well
for m68k.

You need to set up a cross-compiler. The toolchain-source package has some
limitations, I prefer using cross-tools, see this page for instructions:

 http://people.debian.org/~cts/debian-m68k/cross-compile/

Now you only have to tell the debian build system, that you do want to build
packages for m68k. It used to be sufficient to pass an option to debuild,
since recently you also have to set an environment variable, like this:

 DEB_HOST_ARCH=m68k debuild -B -am68k

If you also want to build source packages, omit the -B. 

If you want to build images for just one of the currently nine subarches,
you can uncomment some lines in the flavours section in:
 debian/arch/m68k/defines

The first run of debuild will give you an error message that updating the
configs suceeded, the second run will build the images.