Hi,
After making changes in /brand/config.h file, try running following commands:
rm -rf ./build_dir/target-mips_34kc_uClibc-0.9.33.2/root-ar71xx
rm –rf make./build_dir/target-mips_34kc_uClibc-0.9.33.2/eventslog-1
make package/luci/clean
make package/libbrand/clean
After that, run "make" to start compiling.