Add patch to fix Qcom SNAND driver and move the SNAND patches to
backports directory as they are shared between qualcommax and qualcommbe
target.
Fixes: #17897
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/17900
Signed-off-by: Robert Marko <robimarko@gmail.com>