Seperate FILTER_INTRA from EXT_INTRA experiment

Prepare for the av1/nextgenv2 merge.

Coding gain (%):

               lowres     midres
ext-intra       0.69       0.97
filter-intra    0.67       0.83
both            1.05       1.48

Change-Id: Ia24d6fafb3e484c4f92192e0b7eee5e39f4f4ee6
diff --git a/av1/common/enums.h b/av1/common/enums.h
index ce6032b..b02c814 100644
--- a/av1/common/enums.h
+++ b/av1/common/enums.h
@@ -318,7 +318,7 @@
 
 #endif  // CONFIG_EXT_INTER
 
-#if CONFIG_EXT_INTRA
+#if CONFIG_FILTER_INTRA
 typedef enum {
   FILTER_DC_PRED,
   FILTER_V_PRED,
@@ -330,10 +330,11 @@
   FILTER_D207_PRED,
   FILTER_D63_PRED,
   FILTER_TM_PRED,
-  EXT_INTRA_MODES,
-} EXT_INTRA_MODE;
+  FILTER_INTRA_MODES,
+} FILTER_INTRA_MODE;
+#endif  // CONFIG_FILTER_INTRA
 
-#define FILTER_INTRA_MODES (FILTER_TM_PRED + 1)
+#if CONFIG_EXT_INTRA
 #define DIRECTIONAL_MODES (INTRA_MODES - 2)
 #endif  // CONFIG_EXT_INTRA