This is a massive cleanup needed for vulkan support T68990. It provides:
- More meaningful enums with conversion functions.
- Less hacky supports of arrays and cubemaps (all considered layered).
- More inline with the stateless design of vulkan and modern GL.
- Methods Fallbacks are using framebuffer functions that are wrapped
instead of implementing inside the texture module.
What is not in there:
- API change.
- Samplers support (breaks a few effects).
# Conflicts:
# source/blender/gpu/GPU_texture.h
Now the callbacks are setup for each debug context.
The formating has been reworked to be less verbose and make errors
and warnings stand out from the notifications.
Errors are most of the time sufficiently explicit in their message.
This also remove the support for AMD_debug_output which is 10 years old.
This is related to the Vulkan port T68990.
