CMake: Add the folder "Tablegenning" on llvm-tblgen targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149219 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/cmake/modules/TableGen.cmake b/cmake/modules/TableGen.cmake
index 8c06b05..1b1b172 100644
--- a/cmake/modules/TableGen.cmake
+++ b/cmake/modules/TableGen.cmake
@@ -51,6 +51,7 @@
     add_custom_target(${target}
       DEPENDS ${TABLEGEN_OUTPUT})
     add_dependencies(${target} ${LLVM_COMMON_DEPENDS})
+    set_target_properties(${target} PROPERTIES FOLDER "Tablegenning")
   endif( TABLEGEN_OUTPUT )
 endfunction()