As noted by Jim in a previous vpn_openvpn_export.php commit.  Crafting a URL not user output.  Just following Jim's lead and fixing it here too while here.

Author:		jim-p <jimp@pfsense.org>
Date:		4 months ago (Wed Feb 06 11:55:34 2013)
Commit hash:	dc1799e8c22af75c4f77dc655b5f86dd4f167abc
Parent(s):	da48ad176a


We are crafting a URL, not user output. Use & not &amp; here. Unbreaks export.


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