Remove building files

Author: AmrDeveloper

libcxx/include/CMakeLists.txt

@@ -912,7 +912,6 @@ set(files
   __utility/swap.h
   __utility/to_underlying.h
   __utility/unreachable.h
-  __utility/monostate.h
   __variant/monostate.h
   __vector/comparison.h
   __vector/container_traits.h
@@ -1940,7 +1939,6 @@ set(files
   __cxx03/__utility/swap.h
   __cxx03/__utility/to_underlying.h
   __cxx03/__utility/unreachable.h
-  __cxx03/__utility/monostate.h
   __cxx03/__variant/monostate.h
   __cxx03/__verbose_abort
   __cxx03/algorithm