[NAND]: Avoid reading bad block marker for each page

Add support to prepare bad block table and use the same to
check for bad blocks before reading any page. This would
avoid calling isbad() function for each page and will be more
efficient. With current implementation we are calling isbad()
function around 2048 times for reading 8MB of boot image.

Change-Id: I9b58c43a71de6a3e42997d2f1a150f3330df33c2
CRs-Fixed: 288863
1 file changed