Do not install pre-generated manpages.

Also remove redundant autotools stages.

Early manpages in autoconf 2.52-2.59 are removed from output.
Later ones are regenerated with help2man.

Fixes #182

sysa/autoconf-2.54/stage1.sh

@@ -1,39 +0,0 @@
-# SPDX-FileCopyrightText: 2021 Andrius Štikonas <andrius@stikonas.eu>
-#
-# SPDX-License-Identifier: GPL-3.0-or-later
-
-src_prepare() {
-    rm bin/autoconf.in
-    rm -- Makefile.in */Makefile.in */*/Makefile.in aclocal.m4 configure
-    rm doc/standards.info doc/autoconf.info
-    aclocal-1.7
-    sed -i 's/2.54/2.53/' aclocal.m4
-    cat config/m4.m4 >> aclocal.m4
-    autoconf-2.53
-
-    # Otherwise automake-1.7 fails to find autoconf
-    ln -s "${PREFIX}"/bin/autoconf-2.53 "${PREFIX}"/bin/autoconf
-    automake-1.7
-
-    # Install autoconf data files into versioned directory
-    for file in */*/Makefile.in */Makefile.in Makefile.in; do
-        sed -i '/^pkgdatadir/s:$:-@VERSION@:' "$file"
-    done
-}
-
-src_configure() {
-    ./configure --prefix="${PREFIX}" --program-suffix=-2.54
-}
-
-src_compile() {
-    # Workaround for racy make dependencies
-    make -C bin autom4te
-    make -C lib
-    make MAKEINFO=true
-}
-
-src_install() {
-    make install MAKEINFO=true DESTDIR="${DESTDIR}"
-
-    ln -sf "${PREFIX}"/bin/autoconf-2.54 "${DESTDIR}${PREFIX}"/bin/autoconf
-}