Blender Git Loki

Fix T92462: Cycles crash calculating hair transparency

Need to make sure images needed for hair shaders are loaded
before running the shader.

The naming is a bit misleading, but this is an internal API
and we can change it easily. Submitting minimal patch needed
to fix logic in the code to make it safer to review for 3.0.

Differential Revision: https://developer.blender.org/D13067