Add initial CI and build without PkgConfig
Extend the CMakeLists.txt to fall back to find_library when PkgConfig is not found. This is mainly useful when using an Libibverbs development package from the OS repositories, which places libraries and header files in a standard path.
A basic CI pipeline is added with build stage in three variants:
- Using the
Makefile - Using CMake without PkgConfig
- Using CMake with PkgConfig