Fix checksum inconsistencies between staged and unstaged bwrap bootstrap

- libtool needs autoconf (& possibly other autotools) at make time, to
  generate correct & reproducible manpages
- musl-1.1.24 shouldn't nuke /usr/include in its src_install(), as it
  will remove headers used by other packages later, notably perl.
  (Also, touching the live filesystem in src_install() will be skipped
  if the package is preseeded instead, causing inconsistency.)

steps/musl-1.1.24/pass3.sh

@@ -28,6 +28,5 @@ src_compile() {
 }
 
 src_install() {
-    rm -rf "${PREFIX}/include"
     make PREFIX="${PREFIX}" DESTDIR="${DESTDIR}" install
 }