Add restoration tilesize to frame header

The restoration tilesize can be now chosen as either 256, 128
or 64 at the frame header.

Change-Id: I852fc42afedc053484d657bdca522de73aaacd67
diff --git a/av1/common/alloccommon.c b/av1/common/alloccommon.c
index 09f6135..9183fa5 100644
--- a/av1/common/alloccommon.c
+++ b/av1/common/alloccommon.c
@@ -88,6 +88,7 @@
 }
 
 #if CONFIG_LOOP_RESTORATION
+// Assumes cm->rst_info[p].restoration_tilesize is already initialized
 void av1_alloc_restoration_buffers(AV1_COMMON *cm) {
   int p;
   av1_alloc_restoration_struct(cm, &cm->rst_info[0], cm->width, cm->height);