Move VIDEO_MB to Kconfig.
+++ src/northbridge/amd/gx2/Kconfig (working copy)
@@ -21,6 +21,11 @@
+ default 8
+ depends on NORTHBRIDGE_AMD_GX2
Acked-by: Peter Stuge <peter(a)stuge.se>
But only on the condition that you send a followup patch to change
this option into a choice in the user interface. Please see e.g. how
src/southbridge/via/k8t890/Kconfig implements this. Thanks!