[][mtd: mtk-snand: add read retry to cover uncorrectable ECC when HW is unstable]

Add read retry and add sample_dly by 2 at each retry to cover
uncorrectable ECC, which may happen because of long wiring,
temperature of NAND devices or other board layout issues.


Change-Id: Ibe404e3e4a4017dfa8d31681a60dd8f2c5833e67
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/4777182
1 file changed