Fix warning on launch from QCommandLineParser

Currently kcalc shows next warning on launch:

QCommandLineParser: already having an option named "h"
QCommandLineParser: already having an option named "help-all"
QCommandLineParser: already having an option named "v"

This patch fixes that by removing duplicate code from kcalc, "help" and "version" options are already being added in KAboutData::setupCommandLine

Differential Revision: https://phabricator.kde.org/D26460