[sr-dev] [kamailio/kamailio] sipdump: fixed typo (#2753)

[sergey-safarov]

#### Pre-Submission Checklist
- [x] Commit message has the format required by CONTRIBUTING guide
- [x] Commits are split per component (core, individual modules, libs, utils, ...)
- [x] Each component has a single commit (if not, squash them into one commit)
- [x] No commits to README files for modules (changes must be done to docbook files
in `doc/` subfolder, the README file is autogenerated)

#### Type Of Change
- [x] Small bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds new functionality)
- [ ] Breaking change (fix or feature that would change existing functionality)

#### Checklist:
- [x] PR should be backported to stable branches
- [ ] Tested changes locally
- [ ] Related to issue #XXXX (replace XXXX with an open issue number)

#### Description
fixed `4sipdump(src_port)` handling
You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/2753

-- Commit Summary --

* sipdump: fixed typo

-- File Changes --

M src/modules/sipdump/sipdump_mod.c (2)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/2753.patch
https://github.com/kamailio/kamailio/pull/2753.diff

[Henning Westerholt]

Merged #2753 into master.

[Henning Westerholt]

Thank you