This allows code outside of the render pipeline to make proper
decisions about how the imbuf of render passes are to be handled.
For example, IMB_create_gpu_texture() will now properly select
single channel grayscale texture format for depth pass coming from
multilayer EXR, additionally solving assert in the GPU compositor
code which verifies expected and actual imbuf texture format.
Pull Request: https://projects.blender.org/blender/blender/pulls/117184
11c2028795