Make variables const in write_uniform() and read_uniform()

BUG=aomedia:448

Change-Id: Ie02581a20ca12b24d0a5719a1d9220fb20e25ff7

av1/decoder/decodemv.c

@@ -34,12 +34,10 @@
 #define ACCT_STR __func__
 #if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
 static INLINE int read_uniform(aom_reader *r, int n) {
-  int l = get_unsigned_bits(n);
-  int m = (1 << l) - n;
-  int v = aom_read_literal(r, l - 1, ACCT_STR);
-
+  const int l = get_unsigned_bits(n);
+  const int m = (1 << l) - n;
+  const int v = aom_read_literal(r, l - 1, ACCT_STR);
   assert(l != 0);
-
   if (v < m)
     return v;
   else

av1/encoder/bitstream.c

@@ -98,8 +98,8 @@ static const struct av1_token tx_size_encodings[MAX_TX_DEPTH][TX_SIZES] = {
 
 #if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
 static INLINE void write_uniform(aom_writer *w, int n, int v) {
-  int l = get_unsigned_bits(n);
-  int m = (1 << l) - n;
+  const int l = get_unsigned_bits(n);
+  const int m = (1 << l) - n;
   if (l == 0) return;
   if (v < m) {
     aom_write_literal(w, v, l - 1);

av1/encoder/rdopt.c

@@ -414,7 +414,8 @@ static const REF_DEFINITION av1_ref_order[MAX_REFS] = {
 
 #if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
 static INLINE int write_uniform_cost(int n, int v) {
-  int l = get_unsigned_bits(n), m = (1 << l) - n;
+  const int l = get_unsigned_bits(n);
+  const int m = (1 << l) - n;
   if (l == 0) return 0;
   if (v < m)
     return (l - 1) * av1_cost_bit(128, 0);