NAME
    UnlockLayerInfo -- Unlock the LayerInfo structure.
SYNOPSIS
    UnlockLayerInfo( li )
                     a0
    void UnlockLayerInfo( struct layer_info *);
FUNCTION
    After the operation is complete that required a locklayerinfo,
    unlock the LayerInfo structure so that  other tasks may
    affect the layers.
INPUTS
    li - pointer to the layer_info structure
 BUGS
 SEE ALSO
    locklayerinfo, graphics/layers.h