This reverts commit 4a58c08d67.
The code replicates to a large extent what is already present in iso7816_fidi.c
and I have serious doubts about the correctness of the computation in
its iso7816_3_calculate_wt() function.
Change-Id: I3f26da4e9aa8d7b0f4b4b7992269cf365a643ec7
We now generalize the USB communiction and abandon the 'req_ctx'
structure inherited from openpcd. Instead we use the libosmocore 'msgb'
structure to handle incoming and outgoing USB tranfers. We also use
linuxlist-based msgb-queues for each endpoint.
