problems with getloadavg configuration

[Dave Love]

I've just noticed 2.0.7 and tried to build it on a system without
`getloadavg'.  That fails because it looks for a getloadavg.c and
can't find it.  See the autoconf doc:

 - Macro: AC_FUNC_GETLOADAVG
     Check how to get the system load averages.  To perform its tests
     properly, this macro needs the file `getloadavg.c'; therefore, be
     sure to set the `AC_LIBOBJ' replacement directory properly (see
     *Note Generic Functions::, `AC_CONFIG_LIBOBJ_DIR').

I suggest adding 

AC_CONFIG_LIBOBJ_DIR(pub)

before the use of AC_FUNC_GETLOADAVG [why is it in `Checks for
programs.'?] and putting the getloadavg.c from the Emacs distribution
into pub.  Then in cfenvd.c you can remove the conditional on
HAVE_GETLOADAVG.  (Emacs uses getloadavg unconditionally after maybe
linking its own version, so it is portable.)