drm/amdgpu: free resources on fence usage query

Free the resources if the fence needs to be ignored
during the ratio calculation

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: David M Nieto <david.nieto@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210513174539.27409-1-david.nieto@amd.com