[llvm] [cmake] Expose LLVM_BUILD_TELEMETRY in LLVMConfig.cmake

[mgorny]

Add LLVM_BUILD_TELEMETRY to the list of flags exposed in LLVMConfig.cmake. This fixes telemetry library being misdetected as OFF when building LLDB standalone.

Fixes bac62ee.

---

I guess this also needs a backport to 20.x.

[jh7370]

Looks reasonable to me, but I'll leave it to an LLDB developer to approve, since they'll be better able to confirm this fixes the issue.

[nikic]

LGTM

I guess this also needs a backport to 20.x.

I don't think lldb telemetry is part of 20.x.

[mgorny]

I don't think lldb telemetry is part of 20.x.

Well, I was referring to the fact that bac62ee mentioned backporting the flag, and I believe this to be reasonable part of the flag, even if it weren't really used inside LLVM project at the time.

[llvm-ci]

LLVM Buildbot has detected a new failure on builder lld-x86_64-win running on as-worker-93 while building llvm at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/146/builds/2273

Here is the relevant piece of the build log for the reference

Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM-Unit :: Support/./SupportTests.exe/38/87' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:C:\a\lld-x86_64-win\build\unittests\Support\.\SupportTests.exe-LLVM-Unit-9612-38-87.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=87 GTEST_SHARD_INDEX=38 C:\a\lld-x86_64-win\build\unittests\Support\.\SupportTests.exe
--

Script:
--
C:\a\lld-x86_64-win\build\unittests\Support\.\SupportTests.exe --gtest_filter=ProgramEnvTest.CreateProcessLongPath
--
C:\a\lld-x86_64-win\llvm-project\llvm\unittests\Support\ProgramTest.cpp(160): error: Expected equality of these values:
  0
  RC
    Which is: -2

C:\a\lld-x86_64-win\llvm-project\llvm\unittests\Support\ProgramTest.cpp(163): error: fs::remove(Twine(LongPath)): did not return errc::success.
error number: 13
error message: permission denied



C:\a\lld-x86_64-win\llvm-project\llvm\unittests\Support\ProgramTest.cpp:160
Expected equality of these values:
  0
  RC
    Which is: -2

C:\a\lld-x86_64-win\llvm-project\llvm\unittests\Support\ProgramTest.cpp:163
fs::remove(Twine(LongPath)): did not return errc::success.
error number: 13
error message: permission denied




********************

[JDevlieghere]

Thanks!