Update CMakeLists.txt

Author: mcbarton

unittests/CppInterOp/CMakeLists.txt

@@ -8,7 +8,7 @@ set(clang_libs
 
 foreach(l ${clang_libs})
         find_library(${l} NAMES ${l} HINTS ${LLVM_LIBRARY_DIRS} )
-        mark_as_advanced(${l)
+        mark_as_advanced(${l})
 endforeach(l)
 
 add_cppinterop_unittest(CppInterOpTests