drm/amdgpu: switch from queue_active to queue state

Track the state of the queue rather than simple active vs
not.  This is needed for other states (hung, preempted, etc.).
While we are at it, move the state tracking into the user
queue front end code.

Reviewed-by: Prike Liang <Prike.Liang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>