arm: mvebu: clearfog: initial ClearFog Base variant

Add a unique entry for ClearFog Base variant, reflected in the board
name and adjusted SerDes topology.

Signed-off-by: Joel Johnson <mrjoel@lixil.net>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
index bc5eaa5..161dee9 100644
--- a/arch/arm/mach-mvebu/Kconfig
+++ b/arch/arm/mach-mvebu/Kconfig
@@ -280,4 +280,6 @@
 	default 0
 	depends on SECURED_MODE_IMAGE
 
+source "board/solidrun/clearfog/Kconfig"
+
 endif