Inhibit regular screen blanking on Linux

[NetSysFire]

Quick summary

If there is no screensaver running, rpcs3 can not keep the screen awake, resulting in sudden screen blanking during gameplay.

Details

Vaguely related: #11034

Steps to reproduce:

1. Run a window manager (no desktop environment!), e.g just openbox or in my case awesomewm, which is lacking a screen saver by default. Xorg will blank the screen after I think around 10 minutes.
2. Be able to watch videos in firefox, mpv and emulate games in emulators such as retroarch or even pcsx2 without constant screen blanking.
3. rpcs3 does not inhibit screen blanking.

I am very aware of the "Prevent display sleep while running games" option in the Emulator tab of the settings, but it is grayed out because there is no screen saver running (and thus, the dbus address you check is not bound).
The applications I mentioned above do some possibly Xorg-related magic to stop the screen blanking.

0. Make sure you're running with settings as close to default as possible

Compiled with default options.

1. Please attach RPCS3's log.

n/a, as screen blanking does not have any effect on the applications log.

2. If you describe graphical issue, please provide an RSX capture and a RenderDoc capture that demonstrate it.

n/a

3. Please attach screenshots of your problem.

n/a

4. Please provide comparison with real PS3.

n/a

5. Please provide your system configuration:

• OS: Arch Linux