[PATCH] dc395x - list handling cleanups

Here's another patch in the "try and make the driver readable"
cleanup series. This one cleans up all of the list handling.

Description: Replaced the various hand crafted scsi req lists
(waiting and going in the dcb and free in the acb) and the dcb list
(in the acb) with the generic linux lists. This makes all of the list
related code a *lot* more readable then it was previously.