[CMake] Apple stage1 doesn't need to set libcxx options

LibCXX settings are configured in stage2 so we don't need them here.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278729 91177308-0d34-0410-b5e6-96231b3b80d8

cmake/caches/Apple-stage1.cmake

@@ -27,11 +27,6 @@ set(CLANG_BOOTSTRAP_PASSTHROUGH
 set(BOOTSTRAP_LLVM_ENABLE_LTO ON CACHE BOOL "")
 set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
 
-# LIBCXX Settings
-set(LIBCXX_INSTALL_LIBRARY OFF CACHE BOOL "")
-set(LIBCXX_INSTALL_HEADERS ON CACHE BOOL "")
-set(LIBCXX_OVERRIDE_DARWIN_INSTALL ON CACHE BOOL "")
-
 set(CLANG_BOOTSTRAP_TARGETS
   generate-order-file
   check-all