pxa: fix previous definition on cpu init

start.S:183:1: warning: "ICMR" redefined
In file included from start.S:33:
include/asm/arch/pxa-regs.h:935:1: warning: this is the location of the previous definition
start.S:187:1: warning: "RCSR" redefined
...

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/cpu/pxa/start.S b/cpu/pxa/start.S
index 31f408d..1cdb709 100644
--- a/cpu/pxa/start.S
+++ b/cpu/pxa/start.S
@@ -166,17 +166,13 @@
 /*									    */
 /****************************************************************************/
 /* mk@tbd: Fix this! */
-#if defined(CONFIG_PXA250) || defined(CONFIG_CPU_MONAHANS)
+#undef RCSR
 #undef ICMR
 #undef OSMR3
 #undef OSCR
 #undef OWER
 #undef OIER
-#endif /* CONFIG_PXA250 || CONFIG_CPU_MONAHANS */
-#ifdef CONFIG_PXA250
-#undef RCSR
 #undef CCCR
-#endif /* CONFIG_PXA250 */
 
 /* Interrupt-Controller base address					    */
 IC_BASE:	   .word	   0x40d00000