Drop orphaned ovpn-ccd-convert script

Drop orphaned ovpn-ccd-convert script

This script appeared in the rootfiles for Core Updates 65 and 66, being
released in late 2012 and early 2013. It is not used elsewhere, and
there is no sense in keeping it around on IPFire installations.

Should this patch be accepted, a corresponding 'rm' statement is
necessary in the update.sh script of the Core Update it will go into.

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>
Reviewed-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>