st/mesa: use uint-result for sampling stencil buffers
Otherwise, we end up mismatching the result-type and the sampler-type.
Fixes: 642125ed ("st/mesa: use uint-samplers for sampling stencil buffers")
Otherwise, we end up mismatching the result-type and the sampler-type.
Fixes: 642125ed ("st/mesa: use uint-samplers for sampling stencil buffers")