package/openvpn: bump version to 2.5.4
Release notes:
https://github.com/OpenVPN/openvpn/blob/release/2.5/Changes.rst
Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 13e2912403361b6ff02a460ef8017a9927365a44)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>