Xrx200 IRQ balancing between VPEs

Patches 0901-add-icu-smp-support.patch 0902-enable-external-irqs-for-second-vpe.patch 0903-add-icu1-node-for-smp.patch , compatible with git openwrt snapshot a3ccac6b1d693527befa73532a6cf5abda7134c0 and kernel linux-4.14.96. Should be possible to add them into target/linux/lantiq/patches-4.14, but I didn't test it if the patch folder applies after files folder it should work. Or you can apply them directly on kernel in build_dir/target-mips_24kc_musl/linux-lantiq_xrx200/linux-4.14.96 .