The top-level prepare_docs target is supposed to run before the
generate_docs target.
The repository-level targets like prepare_docs_qtbase now also run
before their respective generate targets.
To achieve that, several intermediate targets had to be introduced.
The dependencies for top-level generate_docs look like this:
/--> generate_top_level_docs_Core --\
generate_docs ---> generate_top_level_docs_Gui -----> prepare_docs
\--> ... --/
The dependencies for repo-level generate_docs_<repo> look like this:
/--> generate_repo_docs_Core
generate_docs_qtbase ---> generate_repo_docs_Gui
\--> ...
generate_repo_docs_Core --\
generate_repo_docs_Gui -----> prepare_docs_qtbase
... --/
Analoguous for qch_docs.
And last but not least, the module-level generate_docs_<module> depends
on prepare_docs_<module>, just like before.
The strangely named top-level install targets have been renamed to
install_html_docs, install_qch_docs and install_docs.
The html_docs target is now merely an alias for generate_docs.
Apart from prepare_docs, the top-level targets do not depend on the
repository-level targets anymore. Targets that are just an alias (docs,
install_docs, ...) have been re-defined to depend just on the respective
top-level targets.
Fixes: QTBUG-87758
Change-Id: I24466d3a252d518a30a2064bf876be881c46231f
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>