openssh: remove deprecated header

srcpkgs/openssh/template

@@ -1,7 +1,7 @@
 # Template file for 'openssh'
 pkgname=openssh
 version=8.0p1
-revision=3
+revision=4
 build_style=gnu-configure
 configure_args="--datadir=/usr/share/openssh
  --sysconfdir=/etc/ssh --without-selinux --with-privsep-user=nobody
@@ -44,6 +44,7 @@ esac
 
 pre_configure() {
 	autoreconf -fi
+	vsed -i -e 's|#include <sys/sysctl.h>||' servconf.c
 }
 
 post_install() {