etnaviv: apply feature overrides in one central location

etnaviv: apply feature overrides in one central location

This way we can just test the feature bits and don't need to spread
the debug overrides to all locations touching a feature.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-By: Wladimir J. van der Laan <laanwj@gmail.com>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>