The generated .tmp_kallsyms.S needs to use .long / .quad for
32/64 bit archs. To know which arch we're compiling for, we
use the preprocessor and BITS_PER_LONG from <asm/types.h>.

Unfortunately, asm/types.h was not safe to include from assembler
files, so lots of #ifndef __ASSEMBLY__ needed to be added - should
be fine now, untested for != i386, though.