bpf: enhance BPF_OBJ_GET_INFO_BY_FD decoder further

bpf: enhance BPF_OBJ_GET_INFO_BY_FD decoder further

* bpf.c (print_ebpf_prog): Remove "decode" argument, all users updated.
(print_bpf_prog_info): Use the minimum of xlated_prog_len values on
entering and exiting syscall as the size of xlated_prog_insns array
to be decoded.  Likewise, use the minimum of nr_map_ids values on entering
and exiting syscall as the size of map_ids array to be decoded.