Improve clarity, remove ambiguity about flag.
Related

• Subfolder handling in /usr/lib #305

Quoting history of this, from #305:

@tresf wrote:

Previously, I used -executable flag. Starting with linuxdepoy, I've tried both the --executable and the --library flags but I'm struggling to keep the expected layout.

@TheAssassin wrote:

[You should] make install the install tree to the AppDir, then use linuxdeploy with --deploy-deps-only to deploy the dependencies of the files in the subdirectories to usr/lib (while also setting their rpath accordingly, but without deploying the libraries themselves again into usr/lib). -l is meant for the manual packaging mode (e.g., when not using make install at all).
[...]
For libraries in directories passed to --deploy-deps-only, linuxdeploy sets the correct rpath and deploys their dependencies into usr/lib.

@tresf wrote:

Great this will fix the problem outright. Will [test and confirm]

@TheAssassin wrote:

I think the flag's help text explains this already: it is used on files already inside the AppDir.

@tresf wrote:

I agree in hindsight, but at first read, it was not obvious... [...]

@TheAssassin wrote:

Thanks for the improved wording. Could you send a PR, please?