buffer: track next_power_of_two changes to size_t.

Author: Christian Hergert

src/mongoc/mongoc-array.c

@@ -56,7 +56,7 @@ _mongoc_array_append_vals (mongoc_array_t *array,
    off = array->element_size * array->len;
    len = (size_t)n_elements * array->element_size;
    if ((off + len) > array->allocated) {
-      next_size = bson_next_power_of_two((uint32_t)(off + len));
+      next_size = bson_next_power_of_two(off + len);
       array->data = bson_realloc(array->data, next_size);
       array->allocated = next_size;
    }

src/mongoc/mongoc-buffer.c

@@ -163,7 +163,7 @@ _mongoc_buffer_append_from_stream (mongoc_buffer_t *buffer,
       }
       buffer->off = 0;
       if (!SPACE_FOR (buffer, size)) {
-         buffer->datalen = bson_next_power_of_two ((uint32_t)(size + buffer->len + buffer->off));
+         buffer->datalen = bson_next_power_of_two (size + buffer->len + buffer->off);
          buffer->data = buffer->realloc_func (buffer->data, buffer->datalen, NULL);
       }
    }
@@ -231,7 +231,7 @@ _mongoc_buffer_fill (mongoc_buffer_t *buffer,
    buffer->off = 0;
 
    if (!SPACE_FOR (buffer, min_bytes)) {
-      buffer->datalen = bson_next_power_of_two ((uint32_t)(buffer->len + min_bytes));
+      buffer->datalen = bson_next_power_of_two (buffer->len + min_bytes);
       buffer->data = buffer->realloc_func (buffer->data, buffer->datalen,
                                            buffer->realloc_data);
    }