mainboard/asus/kfsn4-dre: Remove hard-coded ECC scrub rate

Change-Id: I6ccf44645dabf8ac3674f40d3c5cbcf694aa6237
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: http://review.coreboot.org/8441
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
diff --git a/src/mainboard/asus/kfsn4-dre/Kconfig b/src/mainboard/asus/kfsn4-dre/Kconfig
index 647c074..20ff380 100644
--- a/src/mainboard/asus/kfsn4-dre/Kconfig
+++ b/src/mainboard/asus/kfsn4-dre/Kconfig
@@ -96,10 +96,6 @@
 	bool
 	default y
 
-config AMDMCT_BACKGROUND_SCRUB_RATE
-	hex
-	default 0x06
-
 config MAINBOARD_POWER_ON_AFTER_POWER_FAIL
 	bool
 	default y