Fix compiler error for cpu at91sam9, if lowlevel init is enabled

* Fix compiler error for cpu at91sam9, if lowlevel init is enabled
* use correct ATMEL_ name scheme to define ATMEL_BASE_SDRAMC

Signed-off-by: Jens Scharsig

arch/arm/include/asm/arch-at91/at91sam9_sdramc.h

@@ -20,7 +20,7 @@
 #ifdef __ASSEMBLY__
 
 #ifndef ATMEL_BASE_SDRAMC
-#define ATMEL_BASE_SDRAMC	AT91_SDRAMC0_BASE
+#define ATMEL_BASE_SDRAMC	ATMEL_BASE_SDRAMC0
 #endif
 
 #define AT91_ASM_SDRAMC_MR	ATMEL_BASE_SDRAMC