This was causing crashes/driver resets when odd-dimension textures were
being loaded, due to the size we were uploading being larger than the size
of the higher-level texture calculated by the runtime.
Approximately three or four times now, the issue of pointers being
in an inconsistent state been an issue in the video backend renderers
with regards to tripping up other developers.
Global (ugh) resources are put into a unique_ptr and will always have a
well-defined state of being - null or not null
Texture updates have been moved into TextureCache, while
TMEM updates where moved into bpmem. Code for handling
efb2ram updates was added to TextureCache.
There was a bug for preloaded RGBA8 textures, it only copied
half the texture. The TODO was wrong too.
This checks every TEXTURE_KILL_THRESHOLD frames, to see if the hash for the memory area of the efb copy has hanged. If it has changed, the efb copy can be removed, it wouldn't be used anymore. Before this pr, some efb copies would never be deleted.
Fixes issue https://bugs.dolphin-emu.org/issues/6101 and possibly some other VRAM leaks.
