intel/compiler: don't return non-perspective interp modes on < gfx 6
gfx4/5 don't support these, but lots of TGSI/gallium shaders use LINEAR, but don't seem to care, so just don't use those modes on gfx4/5
This is a precursor patch for crocus.
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gfx4/5 don't support these, but lots of TGSI/gallium shaders use LINEAR, but don't seem to care, so just don't use those modes on gfx4/5
This is a precursor patch for crocus.