qed: Really remove unused field QEDAIOCB.finished

The commit 533ffb1 that removed qed_aiocb_info.cancel said to remove
this but didn't do it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/qed.h

@@ -133,7 +133,6 @@ typedef struct QEDAIOCB {
     int bh_ret;                     /* final return status for completion bh */
     QSIMPLEQ_ENTRY(QEDAIOCB) next;  /* next request */
     int flags;                      /* QED_AIOCB_* bits ORed together */
-    bool *finished;                 /* signal for cancel completion */
     uint64_t end_pos;               /* request end on block device, in bytes */
 
     /* User scatter-gather list */