r8169: fix wrong register use.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Realtek linux nic maintainers <nic_swsd@realtek.com>
diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 05d8178..5990621 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -742,7 +742,7 @@
 	msleep(2);
 	for (i = 0; i < 5; i++) {
 		udelay(100);
-		if (!(RTL_R32(ERIDR) & ERIAR_FLAG))
+		if (!(RTL_R32(ERIAR) & ERIAR_FLAG))
 			break;
 	}