AV1 RT: Use QP-based CDEF for high speed RT

This adds ~25% BDRate improvements with ~8% slowdown
(on speed8 RTC set)

Change-Id: Ia1aeab5775f18d68a16ed97b40fa44a168c2801c
diff --git a/av1/encoder/speed_features.c b/av1/encoder/speed_features.c
index d3b3142..b593121 100644
--- a/av1/encoder/speed_features.c
+++ b/av1/encoder/speed_features.c
@@ -613,6 +613,7 @@
     sf->use_nonrd_pick_mode = 1;
     sf->use_comp_ref_nonrd = 0;
     sf->inter_mode_rd_model_estimation = 2;
+    sf->cdef_pick_method = CDEF_PICK_FROM_Q;
   }
   if (speed >= 8) {
     sf->use_fast_nonrd_pick_mode = 1;