Command line option to hide cursor.

[Hiers]

Adds a command line option to hide the cursor, regardless if any pointer capable devices are available or not.

I have some peripherals plugged in that, for some reason, have the pointer capability available even if they can not control the mouse pointer. This is a quick fix for that. I'm not sure how niche this problem is, but there is an issue regarding an hdmi device with "pointer capabilities" that would be fixed by this PR.

Fixes #299.

P.S. update_capabilities and handle_request_set_cursor seem redundant in setting and unsetting the visibility of the cursor i.e. if you delete one or the other, nothing changes

[Hiers]

BTW when I say delete one or the other, I mean the lines specific to wlr_cursor_unset_image, wlr_cursor_set_xcursor, and wlr_cursor_set_surface.

[emersion]

Maybe there's a better way to deal with this issue? e.g. by disabling the input device via udev?

[mnschipper]

Cage handles the cursor differently than Weston. When I start the same electron application with cage as compositor, there is a cursor in the center of the screen (although only a touch screen is connected, no mouse). When I start the application with weston as compositor, the cursor is NOT displayed.

[Hiers]

Maybe there's a better way to deal with this issue? e.g. by disabling the input device via udev?

Note that I want to use this device. It's a flirc usb for controlling the machine using a remote. I just want to do this without having the pointer on screen but, for some reason, this IR receiver has pointer capabilities.

[emersion]

I've described possible solutions here: #299 (comment)

[Hiers]

Thanks, then I'll close this PR.