drm/amdgpu: prevent spurious warning

The default auto setting for kcq should not generate
a warning.

Fixes: a300de40 ("drm/amdgpu: introduce a new parameter to configure how many KCQ we want(v5)")
Reviewed-by: Kent Russell <kent.russell@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>