Add ddr3lv_support flag to pei_data structure

This will enable DDR3 1.35V support for memory training in
the reference code.  It requires the board to be setup for
1.35V with whatever board-specific GPIOs are available.

Change-Id: I14e4686c20f9610f90678e6e3bece8ba80d8621a
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/1825
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martin@se-eng.com>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/northbridge/intel/sandybridge/pei_data.h b/src/northbridge/intel/sandybridge/pei_data.h
index 34adddc..cabda3f 100644
--- a/src/northbridge/intel/sandybridge/pei_data.h
+++ b/src/northbridge/intel/sandybridge/pei_data.h
@@ -31,7 +31,7 @@
 #define PEI_DATA_H
 
 typedef void (*tx_byte_func)(unsigned char byte);
-#define PEI_VERSION 2
+#define PEI_VERSION 3
 struct pei_data
 {
 	uint32_t pei_version;
@@ -98,6 +98,7 @@
 	 */
 	uint8_t spd_data[4][256];
 	tx_byte_func tx_byte;
+	int ddr3lv_support;
 } __attribute__((packed));
 
 #endif