fbdev: fix error return code in metronomefb_probe()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/metronomefb.c

@@ -690,7 +690,8 @@ static int metronomefb_probe(struct platform_device *dev)
 		goto err_csum_table;
 	}
 
-	if (board->setup_irq(info))
+	retval = board->setup_irq(info);
+	if (retval)
 		goto err_csum_table;
 
 	retval = metronome_init_regs(par);