mtd: nand: remove NAND_COPYBACK macro

It is unused.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

include/linux/mtd/nand.h

@@ -147,8 +147,6 @@ typedef enum {
 #define NAND_BUSWIDTH_16	0x00000002
 /* Chip has cache program function */
 #define NAND_CACHEPRG		0x00000008
-/* Chip has copy back function */
-#define NAND_COPYBACK		0x00000010
 /*
  * Chip requires ready check on read (for auto-incremented sequential read).
  * True only for small page devices; large page devices do not support
@@ -169,11 +167,10 @@ typedef enum {
 #define NAND_SUBPAGE_READ	0x00001000
 
 /* Options valid for Samsung large page devices */
-#define NAND_SAMSUNG_LP_OPTIONS (NAND_CACHEPRG | NAND_COPYBACK)
+#define NAND_SAMSUNG_LP_OPTIONS (NAND_CACHEPRG)
 
 /* Macros to identify the above */
 #define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
-#define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))
 #define NAND_HAS_SUBPAGE_READ(chip) ((chip->options & NAND_SUBPAGE_READ))
 
 /* Non chip related options */