ppc4xx: Only define DDR2 registers for the correct PowerPC variants

Make sure that some SDRAM/DDR2 registers are only defined for the PPC
variants really implementing those registers.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/arch/powerpc/include/asm/ppc4xx-sdram.h b/arch/powerpc/include/asm/ppc4xx-sdram.h
index d9506e2..42eac45 100644
--- a/arch/powerpc/include/asm/ppc4xx-sdram.h
+++ b/arch/powerpc/include/asm/ppc4xx-sdram.h
@@ -363,6 +363,7 @@
 /*
  * Memory controller registers
  */
+#ifdef CONFIG_405EX
 #define SDRAM_BESR	0x00	/* PLB bus error status (read/clear)         */
 #define SDRAM_BESRT	0x01	/* PLB bus error status (test/set)           */
 #define SDRAM_BEARL	0x02	/* PLB bus error address low                 */
@@ -371,11 +372,10 @@
 #define SDRAM_WMIRQT	0x07	/* PLB write master interrupt (test/set)     */
 #define SDRAM_PLBOPT	0x08	/* PLB slave options                         */
 #define SDRAM_PUABA	0x09	/* PLB upper address base                    */
-#ifndef CONFIG_405EX
-#define SDRAM_MCSTAT	0x14	/* memory controller status                  */
-#else
 #define SDRAM_MCSTAT	0x1F	/* memory controller status                  */
-#endif
+#else /* CONFIG_405EX */
+#define SDRAM_MCSTAT	0x14	/* memory controller status                  */
+#endif /* CONFIG_405EX */
 #define SDRAM_MCOPT1	0x20	/* memory controller options 1               */
 #define SDRAM_MCOPT2	0x21	/* memory controller options 2               */
 #define SDRAM_MODT0	0x22	/* on die termination for bank 0             */