[sanitizer_common] Disable sanitizer_redefine_builtins on Apple platforms (#153381) This currently generates many linker warnings of this form, due to defining mem(cpy|move|set) in every object file: ``` ld: warning: '.../build/projects/compiler-rt/lib/interception/CMakeFiles/RTInterception.ios.dir/interception_linux.cpp.o' has malformed LC_DYSYMTAB, expected 6 undefined symbols to start at index 1, found 3 undefined symbols starting at index 1 ``` In order for this to actually replace these symbols on mach-o, they would need a leading underscore, e.g. `.set _memcpy, ___sanitizer_internal_memcpy`. However doing so does not fix the warnings, and furthermore it ends up replacing `REAL(memcpy)` calls with `__sanitizer_internal_memcpy` in places such as `__asan::Allocator::Reallocate`. There is no way on Apple platforms to recreate the intended behaviour, so let's just disable this on them to reduce warning noise. rdar://123771479
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