The message being used previously seemed to indicate something was
wrong with the message. The reality is that we are simply not handling
most of them, and they will end up being forwarded as they come in
osmo-hnbgw.
Related: SYS#5573
Change-Id: If63d942496491f1e9ee454034ec97d25764fde65
Lets add a counterpart for ranap_common_cn that works the same, but
decodes CN/MSC originated messages.
Change-Id: Iad4c2743d4d1ddf8ad49002d1fe6866f22eb9e98
Related: OS#5152