This patch applies on top of the other two (for init problems):

- Uses time to balance interrupt load, not number of transfers.
   One 8-byte lowspeed transfer costs as much as ten same-size
   at full speed ... previous code could overcommit branches.
- Shrinks the code a smidgeon, mostly in the submit path.
- Updates comments, remove some magic numbers, etc.
- Adds some debug dump routines for EDs and TDs, which can
   be rather helpful when debugging!
- Lays ground work for a "shadow" <linux/list.h> TD queue
   (but doesn't enlarge the TD or ED on 32bit cpus)

I'm not sure anyone would have run into that time/balance
issue, though some folk have talked about hooking up lots
of lowspeed devices and that would have made trouble.