drm/amdgpu: fix bug when amdkfd destroys hqd

The wrong define was used to check if the hqd is still active

v2: Don't use SHIFT as the MASK is already shifted

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>