Add a 1.1 compatibility note to the docstrings

Co-Authored-By: ararslan <[email protected]>

Author: fredrikekre

base/sysinfo.jl

@@ -314,6 +314,8 @@ for bsd in (:FreeBSD, :OpenBSD, :NetBSD, :DragonFly)
         !!! note
             Not to be confused with `Sys.isbsd()`, which is `true` on $($s) but also on
             other BSD-based systems. `Sys.$($f)()` refers only to $($s).
+        !!! compat "Julia 1.1"
+            This function requires at least Julia 1.1.
         """
         $f(os::Symbol) = (os === $(QuoteNode(bsd)))
         $f() = $(getfield(@__MODULE__, f)(KERNEL))