The assembly language files reside in architecture-specific
directories, so you need to link /usr/src/include/asm to
/usr/src/linux/include/asm-i386 on PC compatible systems, to
/usr/src/linux/include/asm-sparc on Sun Sparc systems, to
/usr/src/linux/include/asm-ppc on PPC systems, and so on.
You'll also find that you may need to do `make config' as in a
newly-unpacked kernel source tree, to create linux/autoconf.h.