radeonsi: always enable NIR for Civilization 6 to fix corruption

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104602



Cc: 18.3 19.0 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
(cherry picked from commit ae21bdf4)