From: Mathieu Chouquet-Stringer <mchouque@online.fr>

This patch makes the following code work again:

#ifdef STT_REGISTER
                if (info->hdr->e_machine == EM_SPARC ||
                    info->hdr->e_machine == EM_SPARCV9) {
                        /* Ignore register directives. */
                        if (ELF_ST_TYPE(sym->st_info) == STT_REGISTER)
                                break;
                }
#endif

This portion of code is sparc specific and nothing else in modpost.c uses
e_machine meaning cross-compiling for sparc on i386 (or any little endian
machine) is the only way to experience the bug.

Without it, e_machine has the wrong value and modpost then generates a lot
of "*** Warning: \"symbol\" [filename.ko] undefined" messages.