README: Mention SSE4.1 requirement

System: Ensure titles are sanitized for screenshots

CI: Re-enable Flathub pushes

The job can just take longer.. can't be arsed to write a separate
workflow at the moment.

Atualização Português do Brasil (#3218)

Atualizado para a última versão.

CI/Flatpak: Push to Flathub

CI/Flatpak: Disable SDK CFLAGS

It's setting _GLIBCXX_ASSERTIONS in release builds, which has a
performance hit.

FullscreenUI: Add "Open Containing Directory"

OpenGLDevice: Fix incorrect streamed counter

System: Clear cheat list on reset

CPU/CodeCache: Fix page error when rewinding