powerpc, mpc83xx: add DDR SDRAM Timing Configuration 3 definitions

Signed-off-by: Heiko Schocher <hs@denx.de>

Added its mask, too, for intra-file consistency.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>

include/mpc83xx.h

@@ -1053,6 +1053,12 @@
 #define TIMING_CFG2_FOUR_ACT		0x0000003F
 #define TIMING_CFG2_FOUR_ACT_SHIFT	0
 
+/*
+ * TIMING_CFG_3 - DDR SDRAM Timing Configuration 3
+ */
+#define TIMING_CFG3_EXT_REFREC		0x00070000
+#define TIMING_CFG3_EXT_REFREC_SHIFT	16
+
 /*
  * DDR_SDRAM_CFG - DDR SDRAM Control Configuration
  */