sshguard: update to 2.4.3

[filiprojek]

just a version bump
tagging the maintainer @lodvaer

Testing the changes

• I tested the changes in this PR: YES

Local build testing

• I built this PR locally for my native architecture, (x86_64-glibc)
• I built this PR locally for these architectures (if supported. mark crossbuilds):
  • x86_64-musl

[ahesford]

Thanks. The maintainer has not contributed for Void for years, so I adopted the package.