[SCSI] remove scsi_cmnd.eh_state

it's never set to anything, and just three broken drivers are looking
at it and doing odd things.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

include/scsi/scsi_cmnd.h

@@ -38,7 +38,6 @@ struct scsi_cmnd {
 	struct list_head list;  /* scsi_cmnd participates in queue lists */
 
 	struct list_head eh_entry; /* entry for the host eh_cmd_q */
-	int eh_state;		/* Used for state tracking in error handlr */
 	int eh_eflags;		/* Used by error handlr */
 	void (*done) (struct scsi_cmnd *);	/* Mid-level done function */