Driver/DDR: combine ccsr_ddr for 83xx, 85xx and 86xx

Fix ccsr_ddr structure to avoid using typedef. Combine DDR2 and DDR3
structure for 83xx, 85xx and 86xx.

Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/board/freescale/mpc8641hpcn/mpc8641hpcn.c b/board/freescale/mpc8641hpcn/mpc8641hpcn.c
index 0cd9df1..a58b5f9 100644
--- a/board/freescale/mpc8641hpcn/mpc8641hpcn.c
+++ b/board/freescale/mpc8641hpcn/mpc8641hpcn.c
@@ -64,7 +64,7 @@
 {
 #if !defined(CONFIG_SYS_RAMBOOT)
 	volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
-	volatile ccsr_ddr_t *ddr = &immap->im_ddr1;
+	struct ccsr_ddr __iomem *ddr = &immap->im_ddr1;
 
 	ddr->cs0_bnds = CONFIG_SYS_DDR_CS0_BNDS;
 	ddr->cs0_config = CONFIG_SYS_DDR_CS0_CONFIG;