Add something approaching real ELF header files.
Begin merging the common ELF code, beginning with the section name
detection.
Drop automatic generation of .comment section, and in particular the
treatment of .common as a special section (if we decide generating
.comment is still a good idea, we should just do it as a macro.)
Augment the list of known sections, and make it table-driven.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
