Fix DedicatedServerPrintf_fp definition

[MaddTheSane]

Pull Request Type

• GitHub Workflow changes
• Documentation or Wiki changes
• Build and Dependency changes
• Runtime changes
  • Render changes
  • Audio changes
  • Input changes
  • Network changes
  • Other changes

Description

Fix DedicatedServerPrintf_fp to actually match the definition of PrintDedicatedMessage.
This also quiets three warnings about "ISO C++11 does not allow conversion from string literal to 'char *'"

Checklist

• I have tested my changes locally and verified that they work as intended.
• I have documented any new or modified functionality.
• I have reviewed the changes to ensure they do not introduce any unnecessary complexity or duplicate code.
• I understand that by submitting this pull request, I am agreeing to license my contributions under the project's license.

[Lgt2x]

Thanks!