sudo: Compile with '--with-iologdir' to improve build purity

Otherwise it will try to guess the log directory, and the guess might
not be the same if chroot builds are enabled or not.

The gruesome details from m4/sudo.m4:

````
dnl
dnl Where the I/O log files go, use /var/log/sudo-io if
dnl /var/log exists, else /{var,usr}/adm/sudo-io
dnl
AC_DEFUN([SUDO_IO_LOGDIR], [
AC_MSG_CHECKING(for I/O log dir location)
if test "${with_iologdir-yes}" != "yes"; then
iolog_dir="$with_iologdir"
elif test -d "/var/log"; then
iolog_dir="/var/log/sudo-io"
elif test -d "/var/adm"; then
iolog_dir="/var/adm/sudo-io"
else
iolog_dir="/usr/adm/sudo-io"
fi
if test "${with_iologdir}" != "no"; then
SUDO_DEFINE_UNQUOTED(_PATH_SUDO_IO_LOGDIR, "$iolog_dir")
fi
AC_MSG_RESULT($iolog_dir)
])dnl
````

pkgs/tools/security/sudo/default.nix

···
     "--with-rundir=/run/sudo"
     "--with-vardir=/var/db/sudo"
     "--with-logpath=/var/log/sudo.log"
+    "--with-iologdir=/var/log/sudo-io"
     "--with-sendmail=${sendmailPath}"
   ] ++ stdenv.lib.optional withInsults [
     "--with-insults"