[llvm] [Flang-RT][Offload] Always use LLVM-built GTest (PR #143682)

[Michael Kruse via llvm-commits]

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@@ -334,8 +334,8 @@ if (LLVM_INCLUDE_EXAMPLES)
 endif ()
 
 if (FLANG_RT_INCLUDE_TESTS)
-  add_subdirectory(unittests)
   add_subdirectory(test)
+  add_subdirectory(unittests)
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Meinersbur wrote:

Because unittests now adds dependencies to flang-rt-test-depends if unittests are enabled, so the flang-rt-test-depend target must exist.

Previously `test` would use `if (TARGET FlangRTUnitTests)` but `FlangRTUnitTests` was created unconditionally. I could make `FlangRTUnitTests` created conditionally, but I prefer `FlangRTUnitTests` do nothing to not cause a failure when unittests are disabled (CMake will already have given a warning).

https://github.com/llvm/llvm-project/pull/143682