Add support for ISP_FC_GETHINFO, which returns current connection

Add support for ISP_FC_GETHINFO, which returns current connection
topology, speed, loopid, WWPN/WWNN, etc.

Beef up target mode. Add isp_handle_platform_notify_scsi and
isp_handle_platform_notify_fc platform handlers to handle immediate
notifies (isp_handle_platform_notify_scsi is still stubbed out).

In implementation of isp_handle_platform_notify_fc, for IN_ABORT_TASK,
peel off a pending XPT_IMMED_NOTIFY and call xpt_done on it and hope
that somebody upstream is listening.

Make sure on final CTIO2s that we set residual correctly. These are
absolutely crucial. Make sure we set relative offset for each CTIO2
based upon bytes we've already xferred. This is what the private
adjunct datat to the original ATIO is. Note state of command so
we can figure out where to find it if we get an ABORT from the firmware.

Make sure we *always* set CAM_TAG_ACTION_VALID for ATIO2s. Make sure
we keep track of the original lun.

If se sent status (or we're otherwise done with the command), don't
forget to free the adjunct structure.