Enable support for Marvell PHY 88E1510/2

This is only enabled for SpaceCast.

Change-Id: I509785d84b5b2cd169fae62c28b47758929b1785
diff --git a/arch/arm/configs/gfsc100_defconfig b/arch/arm/configs/gfsc100_defconfig
index e1ac049..587fda3 100644
--- a/arch/arm/configs/gfsc100_defconfig
+++ b/arch/arm/configs/gfsc100_defconfig
@@ -196,6 +196,7 @@
 # CONFIG_NET_VENDOR_SMSC is not set
 # CONFIG_NET_VENDOR_STMICRO is not set
 CONFIG_PHYLIB=y
+CONFIG_MARVELL_PHY=y
 CONFIG_ATHEROS_PHY=y
 CONFIG_FIXED_PHY=y
 # CONFIG_WLAN is not set