don't try to control libcxxabi exports on 10.6.8
we are just exporting the entire libcxxabi library
we could make this apply always using the same mechanism as the other
0017-series patch

--- a/libcxxabi/src/CMakeLists.txt.orig	2021-10-27 08:40:22.000000000 -0700
+++ b/libcxxabi/src/CMakeLists.txt	2021-10-27 08:43:52.000000000 -0700
@@ -201,32 +201,6 @@
 
   add_library(cxxabi-reexports INTERFACE)
 
-  # -exported_symbols_list is only available on Apple platforms
-  if (APPLE)
-    function(export_symbols file)
-      target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${file}")
-    endfunction()
-    function(reexport_symbols file)
-      export_symbols("${file}")
-      target_link_libraries(cxxabi-reexports INTERFACE "-Wl,-reexported_symbols_list,${file}")
-    endfunction()
-
-    export_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/itanium-base.exp")
-
-    if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
-      reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/new-delete.exp")
-    endif()
-
-    if (LIBCXXABI_ENABLE_EXCEPTIONS)
-      reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/exceptions.exp")
-
-      if ("${CMAKE_OSX_ARCHITECTURES}" MATCHES "^(armv6|armv7|armv7s)$")
-        reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-sjlj.exp")
-      else()
-        reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-v0.exp")
-      endif()
-    endif()
-  endif()
 endif()
 
 # Build the static library.