Update to linux-support-6.10.6

linux-support-6.10.x included some big changes to the Gencontrol class that we need to adapt to. We've also not yet updated our gencontrol script to use the bundle API, and that is now necessary.

All these changes result in the same binary packages, except that firmware-linux no longer includes a bug-presubj file. It's not at all clear to me how it previously had one, and I don't think this matters much.