The encoding of EF.MSISDN is a bit unstrutured. The encoder function
does not return a valid result since it lacks the parameters
Capability/Configuration2 Record Identifier and Extension5 Record
Identifier, which are mandatory but can be set to 0xFF. Also the
encoder gets its input from pySim-shell, so it should have some
more input validation, especially when the user encodes an empty
string. The encoder and decoder function also do not have unit-tests.
Since the encoder now adds the missing two bytes by isself this does
not have to be done manually anymore, so cards.py needs to be
re-aligned.
For pySim-shell.py the encoder is used from ts_51_011.py. Unfortunately
it is used wrongly there. The optional Alpha Identifier is required
here as well.
Related: OS#4963
Change-Id: Iee5369b3e3ba7fa1155facc8fa824bc60e33b55b