[llvm] Don't test JIT's on z/OS (PR #196580)

[Sean Perry via llvm-commits]

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@@ -41,7 +41,9 @@ add_subdirectory(DebugInfo)
 add_subdirectory(Debuginfod)
 add_subdirectory(Demangle)
 add_subdirectory(DWARFLinkerParallel)
+if (NOT ZOS)
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perry-ca wrote:

Good observation.  I see both in use eg. llvm/cmake/config-ix.cmake.  We should settle on one.  Let's talk with the team, pick one and update all of them.  And leave this as is until we pick.

https://github.com/llvm/llvm-project/pull/196580