Feature: modem uart dfu

[bencefr]

This PR updates nrfjprog libraries to 10.6.0 and uses the new NRFJPROG_modemdfu_dfu_serial_init to create the new probe type for modem programming.

After this change with a Thingy:91 you can do this:

const api = require('pc-nrfjprog-js');

api.programMcuBootDFU(-1, 'nrfjprog/firmware/nrf9160_pca20035_firmware_upgrade_app_0.1.0.hex', 'COM-0', 115200, 12000, console.log, (err) => {
    if (err) {
        console.error(err);
        return;
    }
    api.programModemUartDFU(-1, 'mfw_nrf9160_1.1.1.zip', 'COM-1', 1000000, 12000, console.log, () => {
        console.log('done');
    });
});
...

[bihanssen]

LGTM:+1: