proclist_mutex and proclist_lock into a single adaptive mutex (proc_lock).
Implications:
- Inspecting process state requires thread context, so signals can no longer
be sent from a hardware interrupt handler. Signal activity must be
deferred to a soft interrupt or kthread.
- As the proc state locking is simplified, it's now safe to take exit()
and wait() out from under kernel_lock.
- The system spends less time at IPL_SCHED, and there is less lock activity.
Uploaded scripts work better if they are little endian, as the
card's engine expects, so convert to le first.
Also clean up attach routine a bit (use pa_id and PCI_REVISION
instead of fetching it ourselves).
This makes the driver work on my macppc G4, it can decode and
display video and tuner input. Sound does not seem to work, but
this may be my wonky formac bktr-for-macintosh card.