expand unsupported to all darwin platforms

Author: hnrklssn

test/Interop/Cxx/stdlib/use-std-span.swift

@@ -5,7 +5,7 @@
 // UNSUPPORTED: OS=windows-msvc
 
 // TODO: test failed in macOS PR testing but passes locally: rdar://163049442
-// UNSUPPORTED: OS=macosx
+// UNSUPPORTED: OS_FAMILY=darwin && !CPU=arm64
 
 // REQUIRES: executable_test
 // REQUIRES: std_span