[CMake] Don't apply Export set to clang tools

I can't apply export to tools without getting some strange CMake spew. The behavior here is a bit unexpected. CMake is complaining about static link dependencies not being in the same export set, which shouldn't matter.

In the short term it is easier to just remove the export set (which was just added in r258209) while I sort this out.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@258214 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -447,7 +447,6 @@ endmacro(add_clang_executable)
 macro(add_clang_tool name)
   add_clang_executable(${name} ${ARGN})
   install(TARGETS ${name}
-    EXPORT ClangTargets
     RUNTIME DESTINATION bin
     COMPONENT ${name})