SCARD: Fix GSM authentication on USIM

SCARD: Fix GSM authentication on USIM

scard_gsm_auth() used SIM_CMD_GET_RESPONSE for both SIM and USIM. Convert
the command into USIM_CMD_GET_RESPONSE for USIM.

Since commit eb324600295 ("Fix switching from EAP-SIM to EAP-AKA/AKA'")
EAP-SIM is using the USIM if available. This triggers a probably ancient
bug in scard_gsm_auth(), which results in sending the wrong get response
command to the USIM. Thus, EAP-SIM stopped to work after this change on
USIMs that expect the proper command.

Signed-off-by: Simon Baatz <gmbnomis@gmail.com>