Convert to PREDICTION_MODE for is_directional

Recent code added in EXT_INTRA wasn't compatible with CfL,
because it assumed that the PREDICTION_MODE was the same
for luma and chroma, which is not the case with CfL.

UV_PREDICTION_MODE must be converted to PREDICTION_MODE for
av1_is_directional_mode function.

Change-Id: I10e42e3f4a904905f41205d0018f97807959e841
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index 258eb4a..8130a0f 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -10141,7 +10141,7 @@
   rate2 += write_uniform_cost(
       FILTER_INTRA_MODES, mbmi->filter_intra_mode_info.filter_intra_mode[0]);
 #if CONFIG_EXT_INTRA
-  if (av1_is_directional_mode(mbmi->uv_mode, bsize) &&
+  if (av1_is_directional_mode(get_uv_mode(mbmi->uv_mode), bsize) &&
       av1_use_angle_delta(bsize)) {
     rate2 += write_uniform_cost(2 * MAX_ANGLE_DELTA + 1,
                                 MAX_ANGLE_DELTA + mbmi->angle_delta[1]);
@@ -10979,7 +10979,7 @@
                                       MAX_ANGLE_DELTA + mbmi->angle_delta[0]);
         }
       }
-      if (av1_is_directional_mode(mbmi->uv_mode, bsize) &&
+      if (av1_is_directional_mode(get_uv_mode(mbmi->uv_mode), bsize) &&
           av1_use_angle_delta(bsize)) {
         rate2 += write_uniform_cost(2 * MAX_ANGLE_DELTA + 1,
                                     MAX_ANGLE_DELTA + mbmi->angle_delta[1]);