Revert "[cmake] Xcode 14 warns about -undefined dynamic_lookup; sim…

…ply suppress:"

See root-project/root#11937
for why `-flat_namespace` is bad.

This reverts commit a05d4beded1481a86a65e450826352eb528b03e7.

tools/plugins/example/CMakeLists.txt

@@ -14,7 +14,7 @@ endif()
 
 set_target_properties(clingDemoPlugin PROPERTIES  LIBRARY_OUTPUT_DIRECTORY ".")
 if(APPLE)
-  target_link_libraries(clingDemoPlugin PUBLIC -Wl,-bind_at_load -Wl,-flat_namespace -Wl,-undefined -Wl,suppress)
+  target_link_libraries(clingDemoPlugin PUBLIC -Wl,-bind_at_load -Wl,-undefined -Wl,dynamic_lookup)
 elseif(NOT MSVC)
   target_link_libraries(clingDemoPlugin PUBLIC -Wl,--unresolved-symbols=ignore-in-object-files)
 endif()