[M] Change in libosmo-sigtran[master]: vty: Implement '[no] shutdown' in 'listen' node

Attention is currently required from: fixeria, jolly.

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Change subject: vty: Implement '[no] shutdown' in 'listen' node ......................................................................

Patch Set 1:

(1 comment)

Patchset:

PS1: This is basically the same logic we have for "asp" node, applied to "listen" node. I validated it through vty tests and also did some manual tests to make sure indeed the listening socket is closed and reopened when required by administrative state.