codeintel: Add index configuration for 5 C++ repositories on Cloud

Created by: efritz

Completed:

• https://github.com/sourcegraph/lsif-clang cmake
• https://github.com/dolphin-emu/dolphin cmake
• https://github.com/google/flatbuffers cmake
• https://github.com/genymobile/scrcpy meson
• https://github.com/bitcoin/bitcoin make