net/fm: add 2.5G SGMII support

As auto-negotiation is not supported for 2.5G SGMII, we need
to add a new type PHY_INTERFACE_MODE_SGMII_2500 to differentiate
SGMII-1G and SGMII-2.5G with different setting for auto-negotiation.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/arch/powerpc/include/asm/fsl_serdes.h b/arch/powerpc/include/asm/fsl_serdes.h
index f60cb0a..8e0e190 100644
--- a/arch/powerpc/include/asm/fsl_serdes.h
+++ b/arch/powerpc/include/asm/fsl_serdes.h
@@ -71,6 +71,22 @@
 	INTERLAKEN,
 	QSGMII_SW1_A,		/* Indicates ports on L2 Switch */
 	QSGMII_SW1_B,
+	SGMII_2500_FM1_DTSEC1,
+	SGMII_2500_FM1_DTSEC2,
+	SGMII_2500_FM1_DTSEC3,
+	SGMII_2500_FM1_DTSEC4,
+	SGMII_2500_FM1_DTSEC5,
+	SGMII_2500_FM1_DTSEC6,
+	SGMII_2500_FM1_DTSEC9,
+	SGMII_2500_FM1_DTSEC10,
+	SGMII_2500_FM2_DTSEC1,
+	SGMII_2500_FM2_DTSEC2,
+	SGMII_2500_FM2_DTSEC3,
+	SGMII_2500_FM2_DTSEC4,
+	SGMII_2500_FM2_DTSEC5,
+	SGMII_2500_FM2_DTSEC6,
+	SGMII_2500_FM2_DTSEC9,
+	SGMII_2500_FM2_DTSEC10,
 };
 
 enum srds {