Do not reset the base address of the control endpoint's ring when the second "Set Address" command is issued.  This would lead the HC to reprocess TRBs corresponding to completed transfers.
Do not reset the base address of the control endpoint's ring when
the second "Set Address" command is issued.  This would lead the
HC to reprocess TRBs corresponding to completed transfers.

This was the cause of the "xhci0: NULL xfer pointer" message that
could be seen after attaching a device and reported by naddy@.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars