The qdbd connection to Apalis iMX6 broken on 5.10

Note: Fix for this must include some mechanism for detecting if qdbd binary is really running before writing the /sys files. Currently it's done with sleeps and that's not very stable. This bug will be hidden when QTBUG-63188 is resolved, but the underlying problem remains.

Steps to reproduce:

1. Use Qt installer (test client) to Install Apalis sd card image
   • Qt/Qt Embedded/Boot to Qt Software Stack 5.10.0/Toradex Apalis iMX6/Toradex Apalis iMX6 Linux System
2. Flash it to sdcard using QtCreator
3. Boot Apalis
4. Run "Qt/Tools/qdb/bin/qdb devices"

Expected outcome:

{
    "_version": 1,
    "devices": [
        {
            "hostMac": "fe:45:0b:24:c8:0f",
            "ipAddress": "172.16.58.1",
            "serial": "b2qt-apalis-imx6-00142d4d45a4"
        }
    ],
    "response": "devices"
}

Actual outcome:

{
    "_version": 1,
    "devices": [
    ],
    "response": "devices"
}

Workaround:

1. Make a serial console or ethernet ssh connection to the device
2. "systemctl restart qdbd"