nand: yaffs: Remove the "nand write.yaffs" command

This command is only enabled by one board, complicates the NAND code,
and doesn't appear to have been functioning properly for several
years.  If there are no bad blocks in the NAND region being written
nand_write_skip_bad() will take the shortcut of calling nand_write()
which bypasses the special yaffs handling.  This causes invalid YAFFS
data to be written. See
http://lists.denx.de/pipermail/u-boot/2011-September/102830.html for
an example and a potential workaround.

U-Boot still retains the ability to mount and access YAFFS partitions
via CONFIG_YAFFS2.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>

include/configs/M54418TWR.h

@@ -53,7 +53,6 @@
 #define CONFIG_CMD_MISC
 #define CONFIG_CMD_MII
 #undef CONFIG_CMD_NAND
-#undef CONFIG_CMD_NAND_YAFFS
 #define CONFIG_CMD_NET
 #define CONFIG_CMD_NFS
 #define CONFIG_CMD_PING

include/configs/VCMA9.h

@@ -62,7 +62,6 @@
 #define CONFIG_CMD_PING
 #define CONFIG_CMD_BSP
 #define CONFIG_CMD_NAND
-#define CONFIG_CMD_NAND_YAFFS
 
 #define CONFIG_BOARD_LATE_INIT
 

include/nand.h

@@ -104,11 +104,8 @@ typedef struct nand_erase_options nand_erase_options_t;
 int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
 		       size_t *actual, loff_t lim, u_char *buffer);
 
-#define WITH_YAFFS_OOB	(1 << 0) /* whether write with yaffs format. This flag
-				  * is a 'mode' meaning it cannot be mixed with
-				  * other flags */
-#define WITH_DROP_FFS	(1 << 1) /* drop trailing all-0xff pages */
-#define WITH_WR_VERIFY	(1 << 2) /* verify data was written correctly */
+#define WITH_DROP_FFS	(1 << 0) /* drop trailing all-0xff pages */
+#define WITH_WR_VERIFY	(1 << 1) /* verify data was written correctly */
 
 int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
 			size_t *actual, loff_t lim, u_char *buffer, int flags);