Build: Remove macOS mold and lld linkers support

The mold linker doesn't support macOS anymore. The sold linker
gets no new releases since the Xcode 15+ linker is at par with sold.

https://github.com/bluewhalesystems/sold/issues/50#issuecomment-2076249631
https://github.com/rui314/mold/issues/189#issuecomment-1495288926

Pull Request: https://projects.blender.org/blender/blender/pulls/133634

CMakeLists.txt

@@ -973,7 +973,7 @@ Ensure string operations on fixed size buffers \
 mark_as_advanced(WITH_STRSIZE_DEBUG)
 
 # Compiler tool-chain.
-if(UNIX)
+if(UNIX AND NOT APPLE)
   if(CMAKE_COMPILER_IS_GNUCC)
     option(WITH_LINKER_GOLD "Use ld.gold linker which is usually faster than ld.bfd" ON)
     mark_as_advanced(WITH_LINKER_GOLD)