Cycles: Bump OptiX minimum and release version to 8.0.0

This requires a minimum driver version of 535, however most devices
were already requiring 570 due to the CUDA toolkit version.

The update is required to be able to use an API function for correct
stack size calculation.

Code for older API versions has been removed.

Fix #138185: OSL custom camera errors with OptiX

Pull Request: https://projects.blender.org/blender/blender/pulls/139801

build_files/cmake/Modules/FindOptiX.cmake

@@ -26,14 +26,6 @@ set(_optix_SEARCH_DIRS
   ${OPTIX_ROOT_DIR}
 )
 
-# TODO: Which environment uses this?
-if(DEFINED ENV{PROGRAMDATA})
-  list(APPEND _optix_SEARCH_DIRS
-    "$ENV{PROGRAMDATA}/NVIDIA Corporation/OptiX SDK 7.4.0"
-    "$ENV{PROGRAMDATA}/NVIDIA Corporation/OptiX SDK 7.3.0"
-  )
-endif()
-
 find_path(OPTIX_INCLUDE_DIR
   NAMES
     optix.h

build_files/config/pipeline_config.yaml

@@ -18,7 +18,7 @@ buildbot:
         linux:
             version: '6.4.0'
     optix:
-        version: '7.4.0'
+        version: '8.0.0'
     ocloc:
         version: '101.6557'
     cmake: