This patch  includes the innocuous bits from a larger one that
I'm still working on (mostly unlink fixes):

- updates comments
- flags TDs that were seen in the donelist
- removes some bogus whitespace (at EOL etc) and tabs
- checks for an enumeration issue that might cause trouble
- delays IRQs a bit more aggressively
- shortens TD submit paths a smidgeon (smaller ".o")
- updates some of the debug output
- sanitizes usb_make_path() output on the SA-1111