When using multiple planar probes only the last one would
be visible. The other probes would use the world probe.
Reason is that the data of planar probes are stored in
layered textures. When updating planar probes framebuffers
are created with the correct layer attached.
Vulkan backend missed some code paths to clear a single layer
when clearing a framebuffer where the previous action had depth
write disabled. This PR adds the missing code path.
Pull Request: https://projects.blender.org/blender/blender/pulls/145170
f82e89183e