When KERNEL_SLUB_DEBUG is enabled, build fails due to the KERNEL_STACKDEPOT_MAX_FRAMES missing. Add it. Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be> Link: https://github.com/openwrt/openwrt/pull/18676 Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>