ARM: SPL: Remove NAND_MODE_HW_ECC from spl_nand.c

This detection code doesn't (and can't) do anything currently, so
remove.

Signed-off-by: Tom Rini <trini@ti.com>

arch/arm/include/asm/omap_common.h

@@ -76,7 +76,6 @@ void preloader_console_init(void);
 #define	MMCSD_MODE_UNDEFINED	0
 #define MMCSD_MODE_RAW		1
 #define MMCSD_MODE_FAT		2
-#define NAND_MODE_HW_ECC	3
 
 struct spl_image_info {
 	const char *name;