[CMake] Support running libc++abi tests in CrossWinToARMLinux cache file

Summary:
Now that D71894 has landed, we're able to run libc++abi tests remotely.

For that we can use the same CMake command as before. The tests can be run using `ninja check-cxxabi`.

Reviewers: andreil99, vvereschaka, aorlov

Reviewed By: vvereschaka, aorlov

Subscribers: mgorny, kristof.beyls, ldionne, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D72459