Remove redundant enum

Removed a redundant enum in speed_features.h

Change-Id: Ib70ada91bfcde8353d2122dc093670a21a9d151d
diff --git a/av1/encoder/speed_features.h b/av1/encoder/speed_features.h
index 18fb2d7..867fc5a 100644
--- a/av1/encoder/speed_features.h
+++ b/av1/encoder/speed_features.h
@@ -274,12 +274,6 @@
   DIST_WTD_COMP_DISABLED,
 } UENUM1BYTE(DIST_WTD_COMP_FLAG);
 
-typedef enum {
-  FLAG_SKIP_EIGHTTAP = 1 << EIGHTTAP_REGULAR,
-  FLAG_SKIP_EIGHTTAP_SMOOTH = 1 << EIGHTTAP_SMOOTH,
-  FLAG_SKIP_EIGHTTAP_SHARP = 1 << MULTITAP_SHARP,
-} INTERP_FILTER_MASK;
-
 typedef struct SPEED_FEATURES {
   MV_SPEED_FEATURES mv;