Add == and != operators to KIO::UDSEntry

Summary: I felt it was missing.

Test Plan: ctest

Reviewers: Frameworks, ngraham, dfaure

Reviewed By: ngraham, dfaure

Subscribers: dfaure, pino, ngraham, kde-frameworks-devel

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D23667