shader_recompiler,video_core: Cleanup some GCC and Clang errors

Mostly fixing unused *, implicit conversion, braced scalar init,
fpermissive, and some others.

Some Clang errors likely remain in video_core, and std::ranges is still
a pertinent issue in shader_recompiler

shader_recompiler: cmake: Force bracket depth to 1024 on Clang
Increases the maximum fold expression depth

thread_worker: Include condition_variable

Don't use list initializers in control flow

Co-authored-by: ReinUsesLisp <reinuseslisp@airmail.cc>