tools/bpftool: recognize bpf_prog_info run_time_ns and run_cnt

$ bpftool p s
1: kprobe  tag a56587d488d216c9  gpl run_time_ns 79786 run_cnt 8
	loaded_at 2019-02-22T12:22:51-0800  uid 0
	xlated 352B  not jited  memlock 4096B

$ bpftool --json --pretty p s
[{
        "id": 1,
        "type": "kprobe",
        "tag": "a56587d488d216c9",
        "gpl_compatible": true,
        "run_time_ns": 79786,
        "run_cnt": 8,
        "loaded_at": 1550866971,
        "uid": 0,
        "bytes_xlated": 352,
        "jited": false,
        "bytes_memlock": 4096
    }
]

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>