remsim-bankd doesn't recover after remsim-server restart
I've found this while executing the test suite: remsim-bankd refuses to install a mapping if there is already an existing mapping for that slot. While this makes sense in theory, in practise this means that if the remsim-server looses state (e.g. restart), the old maps in bankd will still exist, and new maps cannot be installed.
I guess we either have to permit new slotmaps to overwrite old ones, or we have to introduce a command by which a [restarting] remsim-server can reset the logical state at a bankd.
The remsim-server could then send that related reset command after a restart. However, this would mean all existing mappings are deleted and re-added, which will break all client-bankd connections happening at the time. So the better approach is probabl to simply overwrite any existing mapping. If the new mapping is identical with the old mapping, we can keep the existing client-bankd communication and the server restart has no implication on any ongoing SIM card communication. Only if the new mapping is different, we'd terminate the connection to the client and replace the old map with the new one.