openvpn: let instances drop to nobody in default config.

This is for security precautions.  As persist_tun and persist_key are
already there, this should not cause compatibility issue.

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

SVN-Revision: 45961

package/network/services/openvpn/files/openvpn.config

@@ -253,6 +253,7 @@ config openvpn sample_server
 	# of the privilege downgrade.
 	option persist_key 1
 	option persist_tun 1
+	option user nobody
 
 	# Output a short status file showing
 	# current connections, truncated
@@ -337,6 +338,7 @@ config openvpn sample_client
 	# Try to preserve some state across restarts.
 	option persist_key 1
 	option persist_tun 1
+	option user nobody
 
 	# If you are connecting through an
 	# HTTP proxy to reach the actual OpenVPN