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/arch/powerpc/cpu/mpc83xx/ecc.c b/arch/powerpc/cpu/mpc83xx/ecc.c
index 6b7f72a..985a024 100644
--- a/arch/powerpc/cpu/mpc83xx/ecc.c
+++ b/arch/powerpc/cpu/mpc83xx/ecc.c
@@ -16,7 +16,7 @@
 {
 	immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 #ifdef CONFIG_SYS_FSL_DDR2
-	ccsr_ddr_t *ddr = &immap->ddr;
+	struct ccsr_ddr __iomem *ddr = &immap->ddr;
 #else
 	ddr83xx_t *ddr = &immap->ddr;
 #endif
@@ -100,7 +100,7 @@
 {
 	immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 #ifdef CONFIG_SYS_FSL_DDR2
-	ccsr_ddr_t *ddr = &immap->ddr;
+	struct ccsr_ddr __iomem *ddr = &immap->ddr;
 #else
 	ddr83xx_t *ddr = &immap->ddr;
 #endif