Empty Info directory node

Emacs uses the texinfo documenting system, but the docs are shipped in a separate package in Alpine Linux. You need to install

apk add texinfo emacs-docs

Then generate the dir index file for Info documenting system.

# run as root
find /usr/share/info/ -name '*.info*' -print0 | xargs -0I{} install-info {} /usr/share/info/dir