Draft: mm-sim-mbim: fallback to AT port when cannot get iccid from MBIM
As discussed in #364 (closed), there are some carriers who distribute SIM cards using A-F in the ICCID. ModemManager supports those ICCIDs.
However, some firmware will drop A-F characters in ICCID (e.g., Intel 7560). It returns a 18-digit ICCID, which will cause parsing error in mm_3gpp_parse_iccid
. So we can fallback to AT port when parsing ICCID has failed.