i965: Fix AA Line Distance Mode in 3DSTATE_SF on Ivybridge.

We were accidentally setting bit 14 in DWord 2 (which is Reserved/MBZ)
rather than bit 14 in DWord 3 (which is AA Line Distance Mode).

There's also no reason to ever set it to legacy mode; the bit is only
used when drawing antialiased lines anyway.  Set it unconditionally.

NOTE: This is a candidate for stable branches.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>

src/mesa/drivers/dri/i965/gen7_sf_state.c

@@ -253,7 +253,6 @@ upload_sf_state(struct brw_context *brw)
    }
    if (ctx->Line.SmoothFlag) {
       dw2 |= GEN6_SF_LINE_AA_ENABLE;
-      dw2 |= GEN6_SF_LINE_AA_MODE_TRUE;
       dw2 |= GEN6_SF_LINE_END_CAP_WIDTH_1_0;
    }
    if (ctx->Line.StippleFlag && intel->is_haswell) {
@@ -264,10 +263,9 @@ upload_sf_state(struct brw_context *brw)
       dw2 |= GEN6_SF_MSRAST_ON_PATTERN;
 
    /* FINISHME: Last Pixel Enable?  Vertex Sub Pixel Precision Select?
-    * FINISHME: AA Line Distance Mode?
     */
 
-   dw3 = 0;
+   dw3 = GEN6_SF_LINE_AA_MODE_TRUE;
 
    /* _NEW_PROGRAM | _NEW_POINT */
    if (!(ctx->VertexProgram.PointSizeEnabled || ctx->Point._Attenuated))