mtd: nand: atmel: prepare for nand spl boot support

Prepare for nand spl boot support. It supports nand software ECC and
hardware PMECC.
This patch is take <drivers/mtd/nand/nand_spl_simple.c> as reference.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/include/nand.h b/include/nand.h
index 84116f4..fc735d1 100644
--- a/include/nand.h
+++ b/include/nand.h
@@ -21,10 +21,16 @@
  * at the same time, so do it here.  When all drivers are
  * converted, this will go away.
  */
+#ifdef CONFIG_SPL_BUILD
+#if defined(CONFIG_NAND_FSL_ELBC) || defined(CONFIG_NAND_FSL_IFC)
+#define CONFIG_SYS_NAND_SELF_INIT
+#endif
+#else
 #if defined(CONFIG_NAND_FSL_ELBC) || defined(CONFIG_NAND_ATMEL)\
 	|| defined(CONFIG_NAND_FSL_IFC)
 #define CONFIG_SYS_NAND_SELF_INIT
 #endif
+#endif
 
 extern void nand_init(void);