a/a/c/arm920t/cpu.c: remove CONFIG_AT91_LEGACY warning

The CONFIG_AT91_LEGACY warning became obsolete due to complete removal of
at91rm9200 arch code in arm920t.

Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/arch/arm/cpu/arm920t/cpu.c b/arch/arm/cpu/arm920t/cpu.c
index be82c87..34adb11 100644
--- a/arch/arm/cpu/arm920t/cpu.c
+++ b/arch/arm/cpu/arm920t/cpu.c
@@ -33,10 +33,6 @@
 #include <command.h>
 #include <asm/system.h>
 
-#ifdef CONFIG_AT91_LEGACY
-#warning Your board is using legacy AT91RM9200 SoC access. Please update!
-#endif
-
 static void cache_flush(void);
 
 int cleanup_before_linux (void)