Don't set the "Protocol" column to "GIOP" until we've decided that the

Don't set the "Protocol" column to "GIOP" until we've decided that the
packet is a GIOP packet.

If it has a GIOP header but doesn't have a version number we handle,
accept it as a GIOP packet; if we don't do that, we should simply return
FALSE *without* changing any of the columns or putting anything into the
protocol tree.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@2615 f5534014-38df-0310-8fa8-9805f1628bb7