mtd: denali: add Denali controller configs to Kconfig

Commit 3eb3e72a3f (nand/denali: Adding Denali NAND driver support)
introduced some new options, and some of them were documented by
commit f9860cf081 (nand/denali: Document CONFIG symbols).

This commit allows users to enable/disable them via Kconfig
with more detailed help docs.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Chin Liang See <clsee@altera.com>
Cc: Scott Wood <scottwood@freescale.com>

doc/README.nand

@@ -215,12 +215,6 @@ Configuration Options:
 
 Platform specific options
 =========================
-   CONFIG_NAND_DENALI
-	Enables the denali.c driver.
-
-   CONFIG_SYS_NAND_DENALI_64BIT
-	Indicates that the Denali NAND controller is the 64-bit variant.
-
    CONFIG_NAND_OMAP_GPMC
 	Enables omap_gpmc.c driver for OMAPx and AMxxxx platforms.
 	GPMC controller is used for parallel NAND flash devices, and can

drivers/mtd/Kconfig

@@ -0,0 +1 @@
+source "drivers/mtd/nand/Kconfig"

drivers/mtd/nand/Kconfig

@@ -0,0 +1,32 @@
+menu "NAND Device Support"
+
+if !SPL_BUILD
+
+config NAND_DENALI
+	bool "Support Denali NAND controller"
+	help
+	  Enable support for the Denali NAND controller.
+
+config SYS_NAND_DENALI_64BIT
+	bool "Use 64-bit variant of Denali NAND controller"
+	depends on NAND_DENALI
+	help
+	  The Denali NAND controller IP has some variations in terms of
+	  the bus interface.  The DMA setup sequence is completely differenct
+	  between 32bit / 64bit AXI bus variants.
+
+	  If your Denali NAND controller is the 64-bit variant, say Y.
+	  Otherwise (32 bit), say N.
+
+config NAND_DENALI_SPARE_AREA_SKIP_BYTES
+	int "Number of bytes skipped in OOB area"
+	depends on NAND_DENALI
+	range 0 63
+	help
+	  This option specifies the number of bytes to skip from the beginning
+	  of OOB area before last ECC sector data starts.  This is potentially
+	  used to preserve the bad block marker in the OOB area.
+
+endif
+
+endmenu