intrabc: enable 16x4 and 4x16 blocks

0.15% gain on the screen_content testset.

BUG=aomedia:998

Change-Id: Ia6484a90b92a00bb0073ecf988b5c164fe8ba84c
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index 5e93d53..ce408cb 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -8668,7 +8668,7 @@
                                        RD_STATS *rd_cost, BLOCK_SIZE bsize,
                                        int64_t best_rd) {
   const AV1_COMMON *const cm = &cpi->common;
-  if (!av1_allow_intrabc(bsize, cm)) return INT64_MAX;
+  if (!av1_allow_intrabc(cm)) return INT64_MAX;
 
   MACROBLOCKD *const xd = &x->e_mbd;
   const TileInfo *tile = &xd->tile;