Fix the incorrect DDR clk freq reporting on 8536DS

On 8536DS board, When the DDR clk is set async mode(SW3[6:8] != 111),
The display is still sync mode DDR freq. This patch try to fix
this. The display DDR freq is now the actual freq in both
sync and async mode.

Signed-off-by: Jason Jin <Jason.jin@freescale.com>
diff --git a/include/asm-ppc/immap_85xx.h b/include/asm-ppc/immap_85xx.h
index 559d6ea..50c9dde 100644
--- a/include/asm-ppc/immap_85xx.h
+++ b/include/asm-ppc/immap_85xx.h
@@ -1552,6 +1552,13 @@
  */
 typedef struct ccsr_gur {
 	uint	porpllsr;	/* 0xe0000 - POR PLL ratio status register */
+#ifdef CONFIG_MPC8536
+#define MPC85xx_PORPLLSR_DDR_RATIO	0x3e000000
+#define MPC85xx_PORPLLSR_DDR_RATIO_SHIFT	25
+#else
+#define MPC85xx_PORPLLSR_DDR_RATIO	0x00003e00
+#define MPC85xx_PORPLLSR_DDR_RATIO_SHIFT	9
+#endif
 	uint	porbmsr;	/* 0xe0004 - POR boot mode status register */
 #define MPC85xx_PORBMSR_HA		0x00070000
 	uint	porimpscr;	/* 0xe0008 - POR I/O impedance status and control register */