stumpy: Add native raminit support

Change-Id: Ibbb056ae209a16533757af925c8c833c94803834
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: https://review.coreboot.org/13662
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
diff --git a/src/mainboard/samsung/stumpy/devicetree.cb b/src/mainboard/samsung/stumpy/devicetree.cb
index df91a724..901711b 100644
--- a/src/mainboard/samsung/stumpy/devicetree.cb
+++ b/src/mainboard/samsung/stumpy/devicetree.cb
@@ -12,6 +12,8 @@
 	# Enable DVI Hotplug with 6ms pulse
 	register "gpu_dp_b_hotplug" = "0x06"
 
+	register "max_mem_clock_mhz" = "666"
+
 	device cpu_cluster 0 on
 		chip cpu/intel/socket_rPGA989
 			device lapic 0 on end