net: designware: s700: Add glue code for S700 mac

This patchs adds glue logic to enable designware mac present on
Action Semi based S700 SoC, Configures SoC specific bits.

Undocumented bit that programs the PHY interface select register
comes from vendor source.

It has been tested on Cubieboard7-lite based on S700 SoC.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 1566b3b..ec3fb49 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -238,6 +238,13 @@
 	  Altera system manager to correctly interface with the PHY.
 	  This code handles those SoC specifics.
 
+config ETH_DESIGNWARE_S700
+	bool "Actins S700 glue driver for Synopsys Designware Ethernet MAC"
+	depends on DM_ETH && ETH_DESIGNWARE
+	help
+	  This provides glue layer to use Synopsys Designware Ethernet MAC
+	  present on Actions S700 SoC.
+
 config ETHOC
 	bool "OpenCores 10/100 Mbps Ethernet MAC"
 	help