compiler: Mark clip/cull distance arrays as compact before lowering.

nir_lower_clip_cull_distance_arrays() marks the combined clip/cull
distance array as compact.  However, when translating in from GLSL
or SPIR-V, we were not marking the original float[] arrays as compact.

We should do so.  That way, we can detect these corner cases properly.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>

src/compiler/spirv/vtn_variables.c

@@ -1444,6 +1444,8 @@ apply_var_decoration(struct vtn_builder *b,
       switch (builtin) {
       case SpvBuiltInTessLevelOuter:
       case SpvBuiltInTessLevelInner:
+      case SpvBuiltInClipDistance:
+      case SpvBuiltInCullDistance:
          var_data->compact = true;
          break;
       case SpvBuiltInFragCoord: