o Reduce the interrupt delay to 2 microframes.
o Follow the spec more closely when updating the overlay qTD in the QH.
o No need to generate an interrupt at the data part of a control
transfer, it's generated by the status transfer.
o Make sure to update the data toggle on short transfers.
o Turn the printf about needing toggle update into a DPRINTF.
o Keep track of what high speed port (if any) a device belongs to
so we can set the transaction translator fields for the transfer.
o Verbosely refuse to open low/full speed pipes that depend on
unimplemented split transaction support.
o Fix various typos in comments.
Obtained from: NetBSD