em357: fix warning by removing unused local variables

Change-Id: I9def63d36ed4fa8bf9cdeeedc18b1b25d0e487d6
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Reviewed-on: http://openocd.zylin.com/184
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

src/flash/nor/em357.c

@@ -757,10 +757,7 @@ static int em357_auto_probe(struct flash_bank *bank)
 
 static int get_em357_info(struct flash_bank *bank, char *buf, int buf_size)
 {
-	int printed;
-	printed = snprintf(buf, buf_size, "em357\n");
-	buf += printed;
-	buf_size -= printed;
+	snprintf(buf, buf_size, "em357\n");
 	return ERROR_OK;
 }