gianfar: add missing iounmap() on error in gianfar_ptp_probe()

Add the missing iounmap() before return from gianfar_ptp_probe()
in the error handling case.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/gianfar_ptp.c

@@ -524,6 +524,7 @@ static int gianfar_ptp_probe(struct platform_device *dev)
 	return 0;
 
 no_clock:
+	iounmap(etsects->regs);
 no_ioremap:
 	release_resource(etsects->rsrc);
 no_resource: