config: upgrade to util-macros 1.8 for additional man page support Use MAN_SUBST now supplied in XORG_MANPAGE_SECTIONS The value of MAN_SUBST is the same for all X.Org packages. Use AC_PROG_SED now supplied by XORG_DEFAULT_OPTIONS The existing statement can now be removed from the configuration file. Use Automake recommened $() for makefile variables. Signed-off-by: Gaetan Nadon <memsize@videotron.ca>