The following patch cleans up the i386 usage of <linux/init.h>.
This remove <linux/init.h> from <asm-i386/system.h> which did not need
it, <asm-i386/highmem.h> which only had it due to an extern using
__init, which is not needed.

This adds <linux/init.h> to <asm-i386/bugs.h> which actually has
numerous __init functions and adds <linux/init.h> to 9 files inside of
arch/i386 which were indirectly including <linux/init.h> previously.