fh < fl --> fh <= fl in od_ec_encode_q15

When lv_map_multi is on,
od_ec_encode_q15 is able to handle the situation of fh == fl

Change-Id: I7c837dda561f1d25b0203c018763dadd0cbbc75a

aom_dsp/entenc.c

@@ -156,7 +156,11 @@ static void od_ec_encode_q15(od_ec_enc *enc, unsigned fl, unsigned fh, int s,
   l = enc->low;
   r = enc->rng;
   OD_ASSERT(32768U <= r);
+#if CONFIG_LV_MAP_MULTI
+  OD_ASSERT(fh <= fl);
+#else
   OD_ASSERT(fh < fl);
+#endif
   OD_ASSERT(fl <= 32768U);
   const int N = nsyms - 1;
   if (fl < 32768U) {