dpdk: add support for segmented mbufs

[mmaatuq]

Make sure these boxes are checked accordingly before submitting your Pull Request -- thank you.

Contribution style:

• I have read the contributing guide lines at
  https://docs.suricata.io/en/latest/devguide/contributing/contribution-process.html

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• I have signed the Open Information Security Foundation contribution agreement at
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Changes (if applicable):

• [] I have updated the User Guide (in doc/userguide/) to reflect the changes made
• [] I have updated the JSON schema (in etc/schema.json) to reflect all logging changes
  (including schema descriptions)
• [] I have created a ticket at

Link to ticket: https://redmine.openinfosecfoundation.org/issues/6012

Describe changes:
When running as a secondary DPDK process, Suricata may receive
segmented (chained) mbufs from the primary application. Previously,
these packets would trigger a warning and potentially be processed
incorrectly since only the first segment was accessible.

Now Suricata handles segmented mbufs by:

1. Attempting to linearize in-place with rte_pktmbuf_linearize()
2. If linearization fails (insufficient tailroom), copying all segments into the packet's internal buffer

A one-time warning is still logged advising users to increase
mbuf size (secondary) or MTU (primary) for better performance.

Ticket: 6012

Provide values to any of the below to override the defaults.

• To use a Suricata-Verify or Suricata-Update pull request,
  link to the pull request in the respective _BRANCH variable.
• Leave unused overrides blank or remove.

SV_REPO=
SV_BRANCH=OISF/suricata-verify#2835
SU_REPO=
SU_BRANCH=

changes since #14541:

• address CR
• rebase to latest main.

[victorjulien]

CI failures are due to the SV test not being rebased, I think.