Add some const qualifiers for BUFFER_SET variables

Change-Id: I1cb389f6bb0e241db6186b9362d9ceed6a8612eb
diff --git a/av1/common/reconinter.h b/av1/common/reconinter.h
index b97f72c..fe06df6 100644
--- a/av1/common/reconinter.h
+++ b/av1/common/reconinter.h
@@ -335,17 +335,18 @@
 // build interintra_predictors for one plane
 void av1_build_interintra_predictors_sbp(const AV1_COMMON *cm, MACROBLOCKD *xd,
                                          uint8_t *pred, int stride,
-                                         BUFFER_SET *ctx, int plane,
+                                         const BUFFER_SET *ctx, int plane,
                                          BLOCK_SIZE bsize);
 
 void av1_build_interintra_predictors_sbuv(const AV1_COMMON *cm, MACROBLOCKD *xd,
                                           uint8_t *upred, uint8_t *vpred,
                                           int ustride, int vstride,
-                                          BUFFER_SET *ctx, BLOCK_SIZE bsize);
+                                          const BUFFER_SET *ctx,
+                                          BLOCK_SIZE bsize);
 
 void av1_build_intra_predictors_for_interintra(
     const AV1_COMMON *cm, MACROBLOCKD *xd, BLOCK_SIZE bsize, int plane,
-    BUFFER_SET *ctx, uint8_t *intra_pred, int intra_stride);
+    const BUFFER_SET *ctx, uint8_t *intra_pred, int intra_stride);
 
 void av1_combine_interintra(MACROBLOCKD *xd, BLOCK_SIZE bsize, int plane,
                             const uint8_t *inter_pred, int inter_stride,