XDP dns rate limit program has static tail call
which requires revert xdp-tool commit:
(039bdea "xdp-loader: Only load the BPF program we need from object files")
XDP dns rate limit program also uses bpf_printk helper which is not
supported on FireBeeOS since kernel CONFIG_BPF_EVENTS which allows user
to do kprobe, uprobe, tracepoint is not enabled, so bpf_printk helper is
not available, so removed bpf_printk
see discussion in [0] xdp-loader load xdp program with bpf tail call result in Bad file descriptor(-9)
[0] https://github.com/xdp-project/xdp-tools/issues/377
Signed-off-by: Vincent Li <vincent.mc.li@gmail.com>
