Run libc++ tests on AArch64 Windows-to-Linux cross builders

[broadwaylamb]

Summary

Now that D85032 has landed, all the tests pass.

[vvereschaka]

Hi Sergej,

I have tested the libc++ tests with our aarch64 target on the Windows builder. It works fine:

Testing Time: 3435.66s
  Unsupported      :  229
  Passed           : 6118
  Expectedly Failed:   52

Thanks.

[gkistanova]

LGTM

[andreil99]

Thanks, Sergej!

buildbot/osuosl/master/config/builders.py

return [
                         ("libunwind",
                          ["python", "bin/llvm-lit.py",
                           "-v", "-vv", "--threads=32",
                           "runtimes/runtimes-bins/libunwind/test"]),
                         ("libc++abi",
                          ["python", "bin/llvm-lit.py",
                           "-v", "-vv", "--threads=32",
                           "runtimes/runtimes-bins/libcxxabi/test"]),
+                        ("libc++",
+                         ['python', 'bin/llvm-lit.py',
+                          '-v', '-vv', '--threads=32',
+                          'runtimes/runtimes-bins/libcxx/test',
+                         ])
                       ],
                       extra_configure_args=[
                         "-DLLVM_TARGETS_TO_BUILD=AArch64",
                         "-DCMAKE_C_COMPILER_TARGET=aarch64-linux-gnu",
                         "-DDEFAULT_SYSROOT=C:/buildbot/.aarch64-ubuntu",
                         "-DLLVM_LIT_ARGS=-v -vv --threads=32",
                         WithProperties("%(remote_test_host:+-DREMOTE_TEST_HOST=)s%(remote_test_host:-)s"),
                         WithProperties("%(remote_test_user:+-DREMOTE_TEST_USER=)s%(remote_test_user:-)s"),