Implement the detailed signal info interface for some Huawei 3GPP modems
including those based on HiSilicon chipsets like the E3276. Known not to
work on many Qualcomm-based Huawei modems like E392, E397, and E367 as
they don't support the ^HCSQ command, but they do support QMI and so
have access to the extended signal interface via QMI.