least the pci device unloadable
- Use ttymalloc() rather than a plain malloc to allocate the
rp->rp_tty ttys. This is now required due to the recent locking
changes to ttys and prevents a panic due to locking an unitialized
t_mtx.
- Allow the pci driver to be unloaded. This involved moving
the call rp_releaseresource() to the end of rp_pcireleaseresource(),
since rp_pcireleaseresource() uses ctlp->dev, which is freed
by rp_releaseresource().
- Allow the generic part of the driver to be unattached by providing
a hook to cancel timeouts.
Glanced at by: obrien