NAME
	LockLayers -- lock all layers from graphics output.

    SYNOPSIS
	LockLayers( li )
	            a0

	void LockLayers( struct Layer_Info *);

    FUNCTION
	First calls LockLayerInfo()
	Make all layers in this layer list locked.

    INPUTS
	li - pointer to Layer_Info structure

    BUGS

    SEE ALSO
	LockLayer(), LockLayerInfo(), graphics/layers.h