Correct assert in leaf frame bit allocation

When the update_type is INTNL_OVERLAY_UPDATE, it should be handled
by the first branch of the if statement.

Change-Id: I5c0c84e76bf4b09ec38b73223113a06029b6fa86
diff --git a/av1/encoder/pass2_strategy.c b/av1/encoder/pass2_strategy.c
index 5ad6158..0cbb60c 100644
--- a/av1/encoder/pass2_strategy.c
+++ b/av1/encoder/pass2_strategy.c
@@ -651,8 +651,7 @@
       gf_group->bit_allocation[arf_pos] = target_frame_size;
       // Note: Boost, if needed, is added in the next loop.
     } else {
-      assert(gf_group->update_type[frame_index] == LF_UPDATE ||
-             gf_group->update_type[frame_index] == INTNL_OVERLAY_UPDATE);
+      assert(gf_group->update_type[frame_index] == LF_UPDATE);
       gf_group->bit_allocation[frame_index] = target_frame_size;
       if (cpi->num_extra_arfs > 0) {
         const int this_budget_reduction =