[SCSI] mac_scsi: Remove unused variable default_instance

This fixes:

drivers/scsi/mac_scsi.c:220:5: warning: "NDEBUG_ABORT" is not defined
drivers/scsi/mac_scsi.c:271:5: warning: "NDEBUG_ABORT" is not defined
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/scsi/mac_scsi.c

@@ -214,13 +214,6 @@ static int __init mac_scsi_setup(char *str) {
 
 __setup("mac5380=", mac_scsi_setup);
 
-/*
- * If you want to find the instance with (k)gdb ...
- */
-#if NDEBUG
-static struct Scsi_Host *default_instance;
-#endif
-
 /*
  * Function : int macscsi_detect(struct scsi_host_template * tpnt)
  *
@@ -268,10 +261,7 @@ int __init macscsi_detect(struct scsi_host_template * tpnt)
     /* Once we support multiple 5380s (e.g. DuoDock) we'll do
        something different here */
     instance = scsi_register (tpnt, sizeof(struct NCR5380_hostdata));
-#if NDEBUG
-    default_instance = instance;
-#endif
-    
+
     if (macintosh_config->ident == MAC_MODEL_IIFX) {
 	mac_scsi_regp  = via1+0x8000;
 	mac_scsi_drq   = via1+0xE000;