ColdFire: Fix board.c warning message

Implicit declaration of nand_init() warning message

Signed-off-by: TsiChung Liew <Tsi-Chung.Liew@freescale.com>

lib_m68k/board.c

@@ -63,6 +63,8 @@
 #include <spi.h>
 #endif
 
+#include <nand.h>
+
 DECLARE_GLOBAL_DATA_PTR;
 
 static char *failed = "*** failed ***\n";