linux-imx

drm/etnaviv: short-circuit perfmon ioctls

The feature implementation isn't stable yet. Reject any attempt to use
the IOCTLs for now. This keeps most of the code in place, so we can stabilize
it in-tree, but keeps userspace from using the feature for now.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>