stmmac: add CSR Clock range selection

This patch adds the CSR Clock range selection.

Original patch from Johannes Stezenbach fixed the CSR
in the stmmac_mdio. We agreed to provide this through
the platform instead of.
Also thanks to Johannes for having tested it on ARM.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/stmmac/stmmac.h b/drivers/net/stmmac/stmmac.h
index d0ddab0..12d1cb0 100644
--- a/drivers/net/stmmac/stmmac.h
+++ b/drivers/net/stmmac/stmmac.h
@@ -78,6 +78,7 @@
 	unsigned int flow_ctrl;
 	unsigned int pause;
 	struct mii_bus *mii;
+	int mii_clk_csr;
 
 	u32 msg_enable;
 	spinlock_t lock;