configs: Disable 4k erase sector size for spansion "s25fs512s" flash

4K erase size is used only in case of hydrid mode which is not
supported on any NXP platform with flash "s25fs512s".
Supported mode is uniform sector, with erase size 256kiB.

Signed-off-by: Ashish Kumar <Ashish.Kumar@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>