tweak anisotropic filtering code

src/mesa/pipe/i915simple/i915_context.c

@@ -158,7 +158,7 @@ i915_get_paramf(struct pipe_context *pipe, int param)
       return 255.0;
 
    case PIPE_CAP_MAX_TEXTURE_ANISOTROPY:
-      return 0.0;
+      return 4.0;
 
    case PIPE_CAP_MAX_TEXTURE_LOD_BIAS:
       return 16.0;

src/mesa/pipe/i915simple/i915_state.c

@@ -212,6 +212,9 @@ i915_create_sampler_state(struct pipe_context *pipe,
    if (sampler->max_anisotropy > 1.0) {
       minFilt = FILTER_ANISOTROPIC;
       magFilt = FILTER_ANISOTROPIC;
+      if (sampler->max_anisotropy > 2.0) {
+         cso->state[0] |= SS2_MAX_ANISO_4;
+      }
    }
    else {
       minFilt = translate_img_filter( sampler->min_img_filter );