[AST] Define placeholder availability for the 6.1 runtime

lorentey · lorentey · commit 284044132ec8 · 2024-06-13T18:00:45.000-07:00
diff --git a/include/swift/AST/RuntimeVersions.def b/include/swift/AST/RuntimeVersions.def
@@ -150,6 +150,11 @@ RUNTIME_VERSION(
   PLATFORM(xrOS, (2, 0, 0))
 )
 
+RUNTIME_VERSION(
+  (6, 1),
+  FUTURE
+)
+
 END_MAJOR_VERSION(6)
 
 // .......................................................................... //
