[llvm] [OFFLOAD] Add plugin with support for Intel oneAPI Level Zero (PR #158900)

[Ross Brunton via llvm-commits]

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@@ -176,6 +176,19 @@ if(NOT (CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64)|(ppc64le)|(aarch64)$"
     list(REMOVE_ITEM LIBOMPTARGET_PLUGINS_TO_BUILD "cuda")
   endif()
 endif()
+if(NOT (CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64)|(AMD64)$" AND
+        CMAKE_SYSTEM_NAME MATCHES "Linux|Windows"))
+  if("level_zero" IN_LIST LIBOMPTARGET_PLUGINS_TO_BUILD)
+    message(STATUS "Not building Level Zero plugin: it is only supported on "
+	           "Linux/Windows x86_64 or ppc64le hosts")
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RossBrunton wrote:

There's still mixed whitespace. Both in this file and `offload/cmake/Modules/LibomptargetGetDependencies.cmake`.

https://github.com/llvm/llvm-project/pull/158900