net/td-system-tools: Update 2.7.4 => 2.7.7

Port changes:

• Update pkg-plist.
• Add USES=gettext-runtime because it's needed for the scripts, even when NLS is turned off.

Changelog:
https://github.com/dreibh/system-tools/blob/td-system-tools-2.7.7/ChangeLog

Commit log:
https://github.com/dreibh/system-tools/compare/td-system-tools-2.7.4...td-system-tools-2.7.7

PR: 296464
Approved by: osa, vvd (Mentors, implicit)