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/mpc8572ds/mpc8572ds.c b/board/freescale/mpc8572ds/mpc8572ds.c
index 2fb4257..5686322 100644
--- a/board/freescale/mpc8572ds/mpc8572ds.c
+++ b/board/freescale/mpc8572ds/mpc8572ds.c
@@ -62,7 +62,7 @@
 phys_size_t fixed_sdram (void)
 {
 	volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
-	volatile ccsr_ddr_t *ddr= &immap->im_ddr;
+	struct ccsr_ddr __iomem *ddr = &immap->im_ddr;
 	uint d_init;
 
 	ddr->cs0_bnds = CONFIG_SYS_DDR_CS0_BNDS;