Screen display is empty with SDL 2.30.50.

[FredBezies]

Describe the bug
Since SDL2 was upgraded on Archlinux (testing for the moment) to SDL2-compat 2.30.50, I got an dialog error box saying: "SDL windows could not be created! Error: Parameter 'renderer' is invalid"

To Reproduce
Steps to reproduce the behavior:

1. Get SDL 2.30.50
2. Build pcem with it
3. Lanch pcem and create a new virtual PC
4. Launch the newly created virtual PC

Expected behavior
Display working.

Screenshots

Host machine

• OS: Archlinux
• Emulator version: commit d1283b91282d522617ac6d29eb0f271ded83ffc