Upgrade tclap to version 1.2.5

[jpyllman]

Version 1.2.2 that is currently in KataGo does not fully support c++20. But it is supposed to be fixed with version 1.2.5. It will also be in 1.4 when that is released.

[lightvector]

Updated to 1.2.5 as of master branch, does it work now?

[jpyllman]

Yes, now I do not get any warnings related to tclap anymore. It actually compiled before. But with warnings.

So, I am compiling with g++-15 and cmake seem to choose -std=gnu++17.
I get some other warnings. Do you look at what kind of warnings you get and try to resolve them??
What C++ version are you aiming for at the moment?? I could do some stricter compiles and try to look at the warnings I get.