intel/fs: Allow constant-propagation into SAMPLEINFO and IMAGE_SIZE

intel/fs: Allow constant-propagation into SAMPLEINFO and IMAGE_SIZE

Without this, we end up with indirect sampler messages all the time
because we don't propagate the texture/image BTI.  This makes debugging
shaders with imageSize or textureSamples in them a pain.

Shader-db results on Ice Lake:

    total instructions in shared programs: 19720612 -> 19720564 (<.01%)
    instructions in affected programs: 4998 -> 4950 (-0.96%)
    helped: 12
    HURT: 0

All affected shaders were compute shaders in Deus Ex: Mankind Divided.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6794>