Now that JFFS2 cleanmarkers are supported on the standard nand_do_upgrade
function we can start using it on bmips.
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
BMIPS is a generic arch that can be used for multiple Broadcom SoCs, each one
with its own specific drivers, so instead of having a huge kernel supporting
all of them, let's switch to a subtarget per SoC like other OpenWrt targets.
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>