mtd: lart: initialize writebufsize

The writebufsize concept was introduce by commit
"0e4ca7e5 mtd: add writebufsize field to mtd_info struct" and it represents
the maximum amount of data the device writes to the media at a time. This is
an important parameter for UBIFS which is used during recovery and which
basically defines how big a corruption caused by a power cut can be.

Set writebufsize to 4 because this drivers writes at max 4 bytes at a time.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [2.6.38+]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/devices/lart.c

@@ -630,6 +630,7 @@ static int __init lart_flash_init (void)
    mtd.name = module_name;
    mtd.type = MTD_NORFLASH;
    mtd.writesize = 1;
+   mtd.writebufsize = 4;
    mtd.flags = MTD_CAP_NORFLASH;
    mtd.size = FLASH_BLOCKSIZE_PARAM * FLASH_NUMBLOCKS_16m_PARAM + FLASH_BLOCKSIZE_MAIN * FLASH_NUMBLOCKS_16m_MAIN;
    mtd.erasesize = FLASH_BLOCKSIZE_MAIN;