chore(cpn): fetch maxlibqt from forked repo at compile time

[elecpower]

Summary of changes:

• use source from EdgeTX/maxLibQt fork
• modify cmake to reference repo
• remove mixed OpenTx implementation

[raphaelcoeffic]

fix bug locally as repo not being actively maintained

Wouldn't it make more sense to fork that repo, add our changes in form of commits on that repo, and either use CMake FetchContent (preferred) or submodule to pull that code?

[elecpower]

fix bug locally as repo not being actively maintained

Wouldn't it make more sense to fork that repo, add our changes in form of commits on that repo, and either use CMake FetchContent (preferred) or submodule to pull that code?

That would provide better attribution but would need an EdgeTx admin to fork and grant permissions for devs to modify.

[raphaelcoeffic]

would need an EdgeTx admin to fork and grant permissions for devs to modify

I forked the repo into EdgeTX Org and invited you as "Maintainer".

[elecpower]

Merged fix for the conditional test into maxLibQt forked repo PR#1

[elecpower]

Merged fix for the macos compile error into maxLibQt forked repo EdgeTX/maxLibQt#2

[elecpower]

@raphaelcoeffic revamped to fetch patched forked repo

[raphaelcoeffic]

@elecpower would you mind if I make a linear history out of your merges on that new repo? I believe it would be easier to handle in case the upstream repo ever gets updated.

Edit: done