Block selection of ultimate builds for SOCs without them #1914
Description
As demonstrated by the configs listed here, not every SOC platform has an ultimate build available. In the installation guide, if the user selects NOR 16M (e.g. because they've verified a 16M flash chip in camera), they will get an invalid firmware build link with no explanation. Better to block this off earlier, perhaps with a note that ultimate builds aren't available on this particular SOC.