[PATCH]: Recognise i586-pc-syllable

[Roland McGrath]

Use libc-ports for this discussion, not libc-alpha.

We can extend what add-on ports can do if necessary.  That is better.
shlib-versions is already covered, that is wholly unnecessary.  In fact,
it would be better to look for abi-tags in sysdeps dirs too and keep
add-on patterns out of the main file.

It looks to me like you could be using a preconfigure file of:

case "$host_os" in
syllable*) elf=yes; libc_config_ok=yes ;;
esac

and not need any configure.in change.