Fix #18189 (Add deprecation of @unix_only, etc. to NEWS) (#18254)

* Fix #18189 (Add deprecation of  etc. to NEWS)

* Remove mentioning of @static, add as a note

* Added reference to Handling Operating System Variation section in manual

* Changed reference numbers

* Change PR number

NEWS.md

@@ -478,6 +478,17 @@ Deprecated or removed
  * The no-op `transpose` fallback has been deprecated. Consider introducing suitable
  `transpose` methods or calling `permutedims(x, [2,1])` ([#13171], [#17075], [#17374]).
 
+ * The following macros have been deprecated ([#16219]):
+ * `@windows` is deprecated in favor of `is_windows()`
+ * `@unix` is deprecated in favor of `is_unix()`
+ * `@osx` is deprecated in favor of `is_apple()`
+ * `@linux` is deprecated in favor of `is_linux()`
+ * `@windows_only` is deprecated in favor of `if is_windows()`
+ * `@unix_only` is deprecated in favor of `if is_unix()`
+ * `@osx_only` is deprecated in favor of `if is_apple()`
+ * `@linux_only` is deprecated in favor of `if is_linux()`
+ * NOTE: Using `@static` could be useful/necessary when used in a function's local scope. See details at the section entitled [Handling Operating System Variation](http://docs.julialang.org/en/latest/manual/handling-operating-system-variation/#man-handling-operating-system-variation) in the manual.
+
 Command-line option changes
 ---------------------------