Remove C99ism in celt/tests/test_unit_mathops.c w/ fixed point build.

celt/tests/test_unit_mathops.c

@@ -209,13 +209,16 @@ void testilog2(void)
    opus_val32 x;
    for (x=1;x<=268435455;x+=127)
    {
-      opus_val32 lg = celt_ilog2(x);
+      opus_val32 lg;
+      opus_val32 y;
+
+      lg = celt_ilog2(x);
       if (lg<0 || lg>=31)
       {
          printf("celt_ilog2 failed: 0<=celt_ilog2(x)<31 (x = %d, celt_ilog2(x) = %d)\n",x,lg);
          ret = 1;
       }
-      opus_val32 y = 1<<lg;
+      y = 1<<lg;
 
       if (x<y || (x>>1)>=y)
       {