mdio_bus: Fix PTR_ERR() usage after initialization to constant
Fix coccinelle warning:
./drivers/net/phy/mdio_bus.c:51:5-12: ERROR: PTR_ERR applied after initialization to constant on line 44
./drivers/net/phy/mdio_bus.c:52:5-12: ERROR: PTR_ERR applied after initialization to constant on line 44
fix this by using IS_ERR before PTR_ERR
Fixes: bafbdd527d56 ("phylib: Add device reset GPIO support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>