Revert "client: make puavo-run-xrandr execute xrandr repeatedly (max 20 times) until success"

This reverts commit d3bad5e32ece9208e2c8120e560ff58b4287afe3.

This fix alone was not enough to fix xrandr-related problems, which, at
least partially might be due to mutual compatibility issues of
puavo-run-xrandr and gnome-settings-daemon (changing display settings
via xrandr-plugin). The whole mess needs re-thinking before any fixes
can be implemented.