Enable kf restrictions at speed 4

Change-Id: I453409d3be3f5fe118b15affde45cb52184aef20

vp9/encoder/vp9_onyx_if.c

diff --git a/vp9/encoder/vp9_onyx_if.c b/vp9/encoder/vp9_onyx_if.c
index d35b739..bfd35b1 100644
--- a/vp9/encoder/vp9_onyx_if.c
+++ b/vp9/encoder/vp9_onyx_if.c
@@ -898,6 +898,8 @@
         sf->subpel_iters_per_step = 1;
         sf->disable_split_var_thresh = 64;
         sf->disable_filter_search_var_thresh = 96;
+        sf->intra_y_mode_mask = INTRA_DC_ONLY;
+        sf->intra_uv_mode_mask = INTRA_DC_ONLY;
         sf->use_fast_coef_updates = 2;
       }
       /*