The SPI max frequency was set to 80MHz, considerably higher than the
vendor clocks it in their firmware (10MHz). Multiple users reported
jffs2 corruption/instability in GitHub issue #10461.
My unit has a W25Q256; datasheet specifies maximum SPI frequency for
read command of 50MHz.
Thanks to @DragonBlueP for suggesting to eliminate m25p,fast-read;
and @MPannen1979 for identifying the problem.
Fixes: #10461
Signed-off-by: Michael Lyle <mlyle@lyle.org>
961e01fc67