dialog: updated old comment to reflect current behaviour

modules/dialog/dlg_hash.c

@@ -720,7 +720,7 @@ dlg_cell_t* dlg_get_by_iuid(dlg_iuid_t *diuid)
  * \param ftag from tag
  * \param ttag to tag
  * \param dir direction
- * \param mode let hash table slot locked if dialog is not found
+ * \param mode let hash table slot locked or not
  * \return dialog structure on success, NULL on failure
  */
 static inline struct dlg_cell* internal_get_dlg(unsigned int h_entry,