AT91: remove CONFIG_PMECC_INDEX_TABLE_OFFSET

This macro is defined, but not referenced by anyone.

I did not touch config_whitelist.txt - the CONFIG will be dropped
by the next re-sync.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

include/configs/at91sam9n12ek.h

@@ -72,7 +72,6 @@
 #define CONFIG_ATMEL_NAND_HW_PMECC
 #define CONFIG_PMECC_CAP		2
 #define CONFIG_PMECC_SECTOR_SIZE	512
-#define CONFIG_PMECC_INDEX_TABLE_OFFSET	0x8000
 
 #define CONFIG_MTD_PARTITIONS
 #define CONFIG_MTD_DEVICE