package/iptraf-ng: bump to version 1.2.1

package/iptraf-ng: bump to version 1.2.1

IPTraf-ng is a console-based network monitoring program for Linux that
displays information about IP traffic. It returns such information as:

- Current TCP connections
- UDP, ICMP, OSPF, and other types of IP packets
- Packet and byte counts on TCP connections
- IP, TCP, UDP, ICMP, non-IP, and other packet and byte counts
- TCP/UDP counts by ports
- Packet counts by packet sizes
- Packet and byte counts by IP address
- Interface activity
- Flag statuses on TCP packets
- LAN station statistics

V1.2.1 fixed multiple issues in V1.1.4 like :
- Introduce packet capturing abstraction: add recvmmsg(),
  TPACKET_V2 and TPACKET_V3 to capture in multigigabit speeds.
- Handling mlock() failures and carry on execution (without
  crashing iptraf-ng).
- Properly account non-IP packets.
- Show dropped packet count.

Signed-off-by: Jugurtha BELKALEM <jugurtha.belkalem@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>