aco: implement image_deref_samples
It used to be that this intrinsic was never created and texture instructions were always used. Signed-off-by:Rhys Perry <pendingchaos02@gmail.com> Reviewed-by:
Samuel Pitoiset <samuel.pitoiset@gmail.com> Fixes: 50881d59 ("compiler/spirv: fix image sample queries") Part-of: <mesa/mesa!9686>