[krbdev.mit.edu #8975] Apparent bug with configure and "make install"

<URL: https://krbdev.mit.edu/rt/Ticket/Display.html?id=8975 >

I bet this only happens with the recently released autoconf 2.70. Near the top
of configure.ac we have:

# If $runstatedir isn't set by autoconf (<2.70), set it manually.
if test x"$runstatedir" = x; then
runstatedir=$localstatedir/run
fi
AC_SUBST(runstatedir)

The compatibility code uses the immediate value of $localstatedir, while
autoconf 2.70 presumably substitutes "${localstatedir}/run". Since we are
sloppy and directly use @localstatedir@ and @runstatedir@ in Makefile.in files,
the real version doesn't work for us.

I will submit a PR next week to add appropriate definitions to config/pre.in
and use $(localstatedir) and $(runstatedir).