atl1c:remove compiling warning

Set wol_ctrl_data to value 0, to remove compiling warning.

Signed-off-by: Jie Yang <jie.yang@atheros.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/atl1c/atl1c_main.c b/drivers/net/atl1c/atl1c_main.c
index be2c6cf..1372e9a 100644
--- a/drivers/net/atl1c/atl1c_main.c
+++ b/drivers/net/atl1c/atl1c_main.c
@@ -2296,7 +2296,7 @@
 	u32 ctrl;
 	u32 mac_ctrl_data;
 	u32 master_ctrl_data;
-	u32 wol_ctrl_data;
+	u32 wol_ctrl_data = 0;
 	u16 mii_bmsr_data;
 	u16 save_autoneg_advertised;
 	u16 mii_intr_status_data;