modem-qmi: disable call list check in case of QMI

Fixes AT's load call list function messing up with the call list in case of both AT+QMI is available for a given modem. Reported here with logs: https://gitlab.com/postmarketOS/pmaports/-/merge_requests/2228#note_623121590

Maybe we can keep this MR open until other issues are reported and fixed in case of AT+QMI setup?