Desktop switch Control+F* grab keys even if disabled

[Bruno Vasselle]

All desktop change Control+F* (ie Control+F1, Control+F2..Control+F12) are X11 grabbed by globalkeyshortcuts, even if disabled by configuration.

To reproduce:
. disable at least one of desktop change (say Control+F5, switch to desktop 5) from "Shortcut Keys" and close
. log out then log in (restarting globalkeyshortcuts is probably not enough)
. run "xev -event keyboard" in a terminal
. observe that when pressing Control+F5, you don't get F5, but a notification relay
. stop globalkeyshortcuts (from "Session Settings" for example)
. with xev, observe that Control+F5 actually reports Control+F5

Workaround:
. bind desktop change to something like Shift+Control+Alt+Scroll_Lock (Control+F13 or Control+F64 apparently does not work, leading to factory reset).
. log out log in
. you're done

System:
Ubuntu 19.10 eoan
lxqt-globalkeys 0.14.1+git20190923-0ubuntu1

Remark:
this really looks like a few years old "https://github.com/lxqt/lxqt/issues/618". However, only desktop change entries seem to be affected (meta+NUMBER in particular are not).