cciss: Remove no longer needed sendcmd reject processing code

Now that the cciss SCSI error handling routines operate with interrupts
enabled, we no longer need to maintain the list of command completions that
sendcmd() might inadvertantly scoop up, since now it only runs at driver init
time, and there won't be any other commands for it to scoop up.  So we
can remove that list and the code that adds to it and processes it.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>