Now that pySim-shell can switch between logical channels, let's state
the currently used logical channel in the prompt.
Change-Id: I45781a6fba205eeb4ac7f58d5cb642b7131bdd88
Related: OS#6230
This file is rather important for 5G SA operation, so we should have
a proper encoder/decoder in place.
Change-Id: I1b37fdfc2807976880b2cafb61951f08eebeb344