We pin when we submit to execlist queue. Balance
the pinning when the submitted queue is cleaned on reset.

Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NThomas Daniel <thomas.daniel@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>