CMake: Added notes pointing to the LLVM CMake documentation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68429 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/cmake/README b/cmake/README
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--- /dev/null
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+See docs/CMake.html for instructions on how to build LLVM with CMake.