Disable lpf across tile in AV1ExtTileTest

This fixes the test failure since af7846ec.

Change-Id: I0905a473841e546b13c30702219efbb0b8b092c6
diff --git a/test/av1_ext_tile_test.cc b/test/av1_ext_tile_test.cc
index 9897558..ab7c250 100644
--- a/test/av1_ext_tile_test.cc
+++ b/test/av1_ext_tile_test.cc
@@ -89,6 +89,9 @@
       // Always use 64x64 max partition.
       encoder->Control(AV1E_SET_SUPERBLOCK_SIZE, AOM_SUPERBLOCK_SIZE_64X64);
 #endif
+#if CONFIG_LOOPFILTERING_ACROSS_TILES
+      encoder->Control(AV1E_SET_TILE_LOOPFILTER, 0);
+#endif
     }
 
     if (video->frame() == 1) {