CMake 4.x compatibility

Building with CMake 4.x (tested with 4.0.2) fails with

Compatibility with CMake < 3.5 has been removed from CMake.

Anything requiring CMake < 3.10 gives the warning

Compatibility with CMake < 3.10 will be removed from a future version of CMake.

CMake 3.10.0 was released more than 6 years ago (https://github.com/Kitware/CMake/releases/tag/v3.10.0), so unless there are requirements for very old versions I would suggest to increase the minimum required version to 3.10