Here is a atch which forces the arch/sparc/boot directory being built 
after all other arch/sparc/* directories. On my 2-way SS20 it makes 
"make -j3 vmlinux" working in the first pass. Someone can test it on 
machine with more CPUs. I post it here for judgement if it is a correct 
way to force the correct order of kernel build. I am not sure if I can 
use variables from the main makefile int the arch/sparc/Makefile.

If it is useful, please merge it into the kernel tree.

Regards,
Krzysztof