mtd: nand: fix incorrect ecc strength values

This fixes a couple of ecc strength values for which I earlier made conservative
guesses, but whose correct values were later determined¹ (thanks Ivan).  Also
sets strength for fsl_ifc_nand, which was merged to mainline after the original
patch that set the strength for all drivers.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040325.html

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/jz4740_nand.c b/drivers/mtd/nand/jz4740_nand.c
index e4147e8..a6fa884 100644
--- a/drivers/mtd/nand/jz4740_nand.c
+++ b/drivers/mtd/nand/jz4740_nand.c
@@ -332,11 +332,7 @@
 	chip->ecc.mode		= NAND_ECC_HW_OOB_FIRST;
 	chip->ecc.size		= 512;
 	chip->ecc.bytes		= 9;
-	chip->ecc.strength	= 2;
-	/*
-	 * FIXME: ecc_strength value of 2 bits per 512 bytes of data is a
-	 * conservative guess, given 9 ecc bytes and reed-solomon alg.
-	 */
+	chip->ecc.strength	= 4;
 
 	if (pdata)
 		chip->ecc.layout = pdata->ecc_layout;