mtd: denali: add Denali NAND driver for SPL

The SPL-mode driver for Denali(Cadence) NAND Flash Memory Controller IP.

This driver requires two CONFIG macros:
 - CONFIG_SPL_NAND_DENALI
     Define to enable this driver.
 - CONFIG_SYS_NAND_BAD_BLOCK_POS
     Specify bad block mark position in the oob space. Typically 0.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Chin Liang See <clsee@altera.com>
Cc: Scott Wood <scottwood@freescale.com>
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 1d9bf48..75c2c06 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -29,4 +29,14 @@
 
 endif
 
+if SPL_BUILD
+
+config SPL_NAND_DENALI
+	bool "Support Denali NAND controller for SPL"
+	help
+	  This is a small implementation of the Denali NAND controller
+	  for use on SPL.
+
+endif
+
 endmenu