Convert CONFIG_NAND_OMAP_ECCSCHEME to Kconfig

The values of CONFIG_NAND_OMAP_ECCSCHEME map to the enum in
include/linux/mtd/omap_gpmc.h for valid ECC schemes.  Make which one we
will use be a choice statement, enumerating the ones which we have
implemented.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/omap3_logic_somlv_defconfig b/configs/omap3_logic_somlv_defconfig
index f7470c1..ece92fe 100644
--- a/configs/omap3_logic_somlv_defconfig
+++ b/configs/omap3_logic_somlv_defconfig
@@ -63,6 +63,7 @@
 CONFIG_SYS_FLASH_PROTECTION=y
 CONFIG_SYS_FLASH_CFI=y
 CONFIG_MTD_RAW_NAND=y
+CONFIG_NAND_OMAP_ECCSCHEME_BCH8_CODE_HW_DETECTION_SW=y
 CONFIG_SYS_NAND_BLOCK_SIZE=0x20000
 CONFIG_SYS_NAND_PAGE_COUNT=0x40
 CONFIG_SYS_NAND_PAGE_SIZE=0x800