Add NEWS

NEWS.md

@@ -34,6 +34,8 @@ New library functions
   * `splitpath(p::String)` function, which is the opposite of `joinpath(parts...)`: it splits a filepath into its components ([#28156]).
   * `isnothing(::Any)` function, to check whether something is a `Nothing`, returns a `Bool` ([#29679]).
   * `getpid(::Process)` method ([#24064]).
+  * Predicate functions `Sys.isfreebsd`, `Sys.isopenbsd`, `Sys.isnetbsd`, and `Sys.isdragonfly` for
+    detecting BSD systems have been added ([#30249]).
 
 Standard library changes
 ------------------------
@@ -80,3 +82,4 @@ Deprecated or removed
 [#28878]: https://github.com/JuliaLang/julia/issues/28878
 [#29440]: https://github.com/JuliaLang/julia/issues/29440
 [#29442]: https://github.com/JuliaLang/julia/issues/29442
+[#30249]: https://github.com/JuliaLang/julia/issues/30249