drivers: net: cpsw: remove superfluous assignment.

In

	int ret = A;
	ret = B;

the first assignment has not effect.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/cpsw.c b/drivers/net/cpsw.c
index b72258f..e2395db 100644
--- a/drivers/net/cpsw.c
+++ b/drivers/net/cpsw.c
@@ -949,7 +949,7 @@
 {
 	void *buffer;
 	int len;
-	int ret = -EAGAIN;
+	int ret;
 
 	ret = cpdma_process(priv, &priv->rx_chan, &buffer, &len);
 	if (ret < 0)