Revert "drm/etnaviv: Expose a few more chipspecs to userspace"

This reverts commit 1dccdba0.

In userspace a different approach was choosen - hwdb. As a result, there
is no need for these values.

Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Reviewed-by: Tomeu Vizoso <tomeu@tomeuvizoso.net>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>