Disable Strict Bourne shell mode for /etc/rc and /etc/netstart to be

able to use ksh syntax within these scripts. This way init doesn't
need to be changed, which starts /etc/rc using /bin/sh and people
can still use "sh /etc/netstart ifname".
Idea from and OK halex@
OK deraadt@ krw@ guenther@

src/etc/netstart

@@ -1,6 +1,9 @@
 #!/bin/sh -
 #
-#	$OpenBSD: netstart,v 1.152 2015/07/19 23:42:58 florian Exp $
+#	$OpenBSD: netstart,v 1.153 2015/07/20 06:59:39 rpe Exp $
+
+# Turn off Strict Bourne shell mode.
+set +o sh
 
 # Strip comments (and leading/trailing whitespace if IFS is set) from a file
 # and spew to stdout.

src/etc/rc

@@ -1,9 +1,12 @@
-#	$OpenBSD: rc,v 1.453 2015/07/19 04:44:36 rpe Exp $
+#	$OpenBSD: rc,v 1.454 2015/07/20 06:59:39 rpe Exp $
 
 # System startup script run by init on autoboot or after single-user.
 # Output and error are redirected to console by init, and the console is the
 # controlling terminal.
 
+# Turn off Strict Bourne shell.
+set +o sh
+
 # Subroutines (have to come first).