A while back there were some reports of ohci reporting a "bad entry"
diagnostic, mostly with ISO transfers, which were mysterious until
I recently found an easy way to reproduce it.

This patch:

  - Fixes at least one cause of that "bad entry" diagnostic by
    waiting for INTR_WDH before completing ED unlink processing.
    (Else URB unlinking could free TDs on the donelist, so the
    WDH processing would see those entries as "bad".)

  - Merges the patch from Darwin Rambo <drambo@broadcom.com>,
    coping with CPUs that can't do 16 bit accesses (MIPS).

  - Renames a function as start_ed_unlink(), matching its role.

  - Fixes minor debug output issues, including a FIXME to tell
    more info about TDs on the periodic schedule.  And adding
    some missing newlines (makes this patch seem big).

Nobody's complained much about that "bad entry" issue lately, but
if necessary that part would be particularly easy to split out.

Please merge to the next kernel that gets USB patches.