netsniff-ng nlmsg: Print netlink protocol name
nlmsg proto handler can't identify Netlink protocol from nlmsghdr, so
sockaddr_ll can be used to get it.
Also renamed [proto -> handler] member in pkt_buff struct, which is more
understandable.
Example:
>U nlmon0 4756 1429891435s.14505747ns
[ NLMSG Proto 0 (RTNETLINK), Len 1160, Type 0x0010 (0x10), Flags 0x0002 (MULTI), Seq-Nr
1429891436, PID 31613 ]
Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
[tklauser: Handle usage of NETLINK_SOCK_DIAG with pre 3.10 kernel
headers, fix nl_proto2str() return value, formatting changes]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>