Convert CONFIG_SYS_FAULT_ECHO_LINK_DOWN to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_FAULT_ECHO_LINK_DOWN

Cc: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/edminiv2_defconfig b/configs/edminiv2_defconfig
index abdc48b..bbc7b41 100644
--- a/configs/edminiv2_defconfig
+++ b/configs/edminiv2_defconfig
@@ -34,6 +34,7 @@
 CONFIG_ENV_IS_IN_FLASH=y
 CONFIG_ENV_ADDR=0xFFF84000
 CONFIG_NETCONSOLE=y
+CONFIG_SYS_FAULT_ECHO_LINK_DOWN=y
 CONFIG_SYS_IDE_MAXBUS=1
 CONFIG_SYS_IDE_MAXDEVICE=1
 CONFIG_SYS_ATA_BASE_ADDR=0xf1080000