winsys/radeon: fix nop packet padding for hawaii

winsys/radeon: fix nop packet padding for hawaii

The initial firmware for hawaii does not support type3 nop packet.
Detect the new hawaii firmware with query RADEON_INFO_ACCEL_WORKING2.
If the returned value is 3, then the new firmware is used.

This patch uses type2 for the old firmware and type3 for the new firmware.

It fixes the cases when the old firmware is used and the user wants to
manually enable acceleration.
The two possible scenarios are:
 - the kernel has no support for the new firmware.
 - the kernel has support for the new firmware but only the old firmware
   is available.

Additionaly this patch disables GPU acceleration on hawaii if the kernel
returns a value < 2. In this case the kernel hasn't the required fixes
for proper acceleration.

v2:
 - Fix indentation
 - Use private struct radeon_drm_winsys instead of public struct radeon_info
 - Rename r600_accel_working2 to accel_working2

v3:
 - Use type2 nop packet for returned value < 3

v4:
 - Fail to initialize winsys for returned value < 2

Cc: mesa-stable@lists.freedesktop.org
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Marek Olšák <marek.olsak@amd.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Andreas Boll <andreas.boll.dev@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>