FreeBSD port (58): config support

[Roland McGrath]

> The updated configuration support. Indeed defining the default version in
> shlib-versions makes it unnecessary to define a default value for oldest_abi.

> 
> ChangeLog:
> 2002-09-04  Bruno Haible  <bruno@clisp.org>
> 
> 	* configure.in: Don't require --enable-hacker-mode for FreeBSD.
> 	* shlib-versions (libm, libc): Define as version 1 on FreeBSD.

Please put some comments in the file about what FreeBSD reality the soname
corresponds to.  Your log entry failed to mention the DEFAULT entry.  There
is no need to additional entries when there is a default, i.e. the existing
catch-all lines that have the soname you want are fine because when the
third column is absent the DEFAULT value is used (that's what it's for).