The Vulkan implementation needs a directory for each architectural
layer, similar to the OpenGL ES stack. The entire rendering stack is
duplicated, leaving only Reactor common between them:

Renderer -> Device
Shader -> Pipeline
Common -> System
Main -> WSI

Bug b/117152542

Change-Id: I9c26b23654016d637f88ec2416f019ef65b9afbd
Reviewed-on: https://swiftshader-review.googlesource.com/c/21248Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>