net: ethernet: Fix a unused function warning.

Fix the following compile warning:

drivers/net/ethernet/microchip/lan743x_main.c:2964:12: warning: ‘lan743x_pm_suspend’ defined but not used [-Wunused-function]
 static int lan743x_pm_suspend(struct device *dev)
drivers/net/ethernet/microchip/lan743x_main.c:2987:12: warning: ‘lan743x_pm_resume’ defined but not used [-Wunused-function]
 static int lan743x_pm_resume(struct device *dev)

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>