[SCSI] aha152x: fix init suspiciously returned 1, it should follow 0/-E convention

Reported-by: Frank de Jong <[e-mail]>
> [1.] One line summary of the problem:
> linux-2.6.25.3, aha152x'->init suspiciously returned 1, it should
> follow 0/-E convention. The module / driver works okay. Unloading the
> module is impossible.

The driver is apparently returning 0 on failure and 1 on success.
That's a bit unfortunate. Fix it by altering to -ENODEV and 0.

Cc: Stable Tree <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/aha152x.c

···
 			iounmap(p);
 		}
 		if (!ok && setup_count == 0)
-			return 0;
+			return -ENODEV;
 
 		printk(KERN_INFO "aha152x: BIOS test: passed, ");
 #else
···
 #endif
 	}
 
-	return 1;
+	return 0;
 }
 
 static void __exit aha152x_exit(void)