inv_txfm_add_32x32: Cleanup

Only DCT_DCT and IDTX types are allowed.

Change-Id: Id354ff9ebf617164e0fc8579d667ff81488712b8

av1/common/idct.c

diff --git a/av1/common/idct.c b/av1/common/idct.c
index dcdbbed..82352ff 100644
--- a/av1/common/idct.c
+++ b/av1/common/idct.c
@@ -225,7 +225,7 @@
 
 static void highbd_inv_txfm_add_32x32(const tran_low_t *input, uint8_t *dest,
                                       int stride, const TxfmParam *txfm_param) {
-  int bd = txfm_param->bd;
+  const int bd = txfm_param->bd;
   const TX_TYPE tx_type = txfm_param->tx_type;
   const int32_t *src = cast_to_int32(input);
   switch (tx_type) {
@@ -236,21 +236,7 @@
 
     // The optimised version only supports DCT_DCT, so force use of
     // the C version for all other transform types.
-    case ADST_DCT:
-    case DCT_ADST:
-    case ADST_ADST:
-    case FLIPADST_DCT:
-    case DCT_FLIPADST:
-    case FLIPADST_FLIPADST:
-    case ADST_FLIPADST:
-    case FLIPADST_ADST:
     case IDTX:
-    case V_DCT:
-    case H_DCT:
-    case V_ADST:
-    case H_ADST:
-    case V_FLIPADST:
-    case H_FLIPADST:
       av1_inv_txfm2d_add_32x32_c(src, CONVERT_TO_SHORTPTR(dest), stride,
                                  tx_type, bd);
       break;