drm/amdkfd: Fix resource leak in criu restore queue

To avoid memory leaks, release q_extra_data when exiting the restore queue.
v2: Correct the proto (Alex)

Signed-off-by: Jesse Zhang <jesse.zhang@amd.com>
Reviewed-by: Tim Huang <tim.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>