Revert "Teach the CMake build system to run lit's test suite. These can be run"

This reverts r257221.

This caused several build bot failures

* It looks like some of the tests don't work correctly under Windows
* It looks like the lit per test timeout tests fail

So I'm reverting for now. Once the above failures are fixed running
lit's tests can be enabled again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257268 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed