doc/go1.17: mention SYS_WAIT6/WEXITED on NetBSD

For #13987
For #16028
For #44513

Change-Id: I7a73446fcc80a01fa6de24eec1e5b993e543be37
Reviewed-on: https://go-review.googlesource.com/c/go/+/323489
Trust: Ian Lance Taylor <[email protected]>
Reviewed-by: Emmanuel Odeke <[email protected]>

Author: ianlancetaylor

doc/go1.17.html

@@ -651,6 +651,14 @@ <h3 id="minor_library_changes">Minor changes to the library</h3>
       DragonFly and all OpenBSD systems (it was already defined on
       some OpenBSD systems and all FreeBSD, NetBSD, and Linux systems).
     </p>
+
+    <p><!-- CL 315281 -->
+      The constants <code>SYS_WAIT6</code> and <code>WEXITED</code>
+      are now defined on NetBSD systems (<code>SYS_WAIT6</code> was
+      already defined on DragonFly and FreeBSD systems;
+      <code>WEXITED</code> was already defined on Darwin, DragonFly,
+      FreeBSD, Linux, and Solaris systems).
+    </p>
   </dd>
 </dl><!-- syscall -->