Draft: qcom-soc: add support for QRTR + MHI based modems

This allows MHI-based modems using QRTR for QMI to communicate with the ModemManager executable using the existing qcom-soc plugin.

Additionally, many fixes to the ModemManager core were added to allow the successful operation of the plugin:

• In general, anything gated by g_strcmp0 (..., "ipa") now also needs to check for the MHI network driver, "mhi_net". DPM port open is not required for this target, however.
• QMAPv5 definitons for checksum offload are added to allow creating the RMNET devices using the new QMAPv5 protocol. ( + Corresponding patch in libqmi to allow QMAPv5 link creation)
• Endpoint interface ID for PCIE type is updated to the correct value
• QMI endpoint initialization is delayed until after modem port organization. This is because with QRTR-based targets, we cannot know what ENDPOINT_TYPE value to use until we know what kind of transport device is in use. Once modem ports are organized, we will know the transport driver name, allowing us to determine the correct ENDPOINT_TYPE value to use for initialization.