Describe the bug
Ethernet has a 64-byte minimum frame size. Frames smaller than this (for example, plain TCP ACK without options on IPv4) need to be padded to 64 bytes (60 bytes excluding FCS). tcpreplay-edit (but not tcpreplay) will incorrectly include Ethernet padding bytes in the IP length field.

To Reproduce
Steps to reproduce the behavior:

1. Start tcpdump on the interface where tcpreplay-edit will be run
2. tcpreplay-edit any pcap with ethernet padding bytes to the interface
3. Observe that the replayed packets have the IP length field modified to include padding bytes (Wireshark should complain a lot)

Expected behavior
tcpreplay-edit (like tcpreplay) does not modify the IP length field and keeps the padding.

System (please complete the following information):

• OS: Fedora 39 (Linux 6.6.9-200.fc39.x86_64)
• Tcpreplay Version: latest master, currently 43693c4

Additional context
None